diff --git a/core/java/android/app/time/LocationTimeZoneManager.java b/core/java/android/app/time/LocationTimeZoneManager.java
index 066aadae14760..f506f12a7ba03 100644
--- a/core/java/android/app/time/LocationTimeZoneManager.java
+++ b/core/java/android/app/time/LocationTimeZoneManager.java
@@ -49,31 +49,6 @@ public final class LocationTimeZoneManager {
      */
     public static final String SHELL_COMMAND_STOP = "stop";
 
-    /**
-     * A shell command that can put providers into different modes. Takes effect next time the
-     * service is started.
-     */
-    public static final String SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE =
-            "set_provider_mode_override";
-
-    /**
-     * The default provider mode.
-     * For use with {@link #SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE}.
-     */
-    public static final String PROVIDER_MODE_OVERRIDE_NONE = "none";
-
-    /**
-     * The "simulated" provider mode.
-     * For use with {@link #SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE}.
-     */
-    public static final String PROVIDER_MODE_OVERRIDE_SIMULATED = "simulated";
-
-    /**
-     * The "disabled" provider mode (equivalent to there being no provider configured).
-     * For use with {@link #SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE}.
-     */
-    public static final String PROVIDER_MODE_OVERRIDE_DISABLED = "disabled";
-
     /**
      * A shell command that tells the service to record state information during tests. The next
      * argument value is "true" or "false".
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index fc2bdf3a4610f..6927801ad40f2 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -1637,32 +1637,22 @@
          config_timeZoneRulesUpdateTrackingEnabled are true.] -->
     <integer name="config_timeZoneRulesCheckRetryCount">5</integer>
 
-    <!-- Whether the geolocation time zone detection feature is enabled. -->
+    <!-- Whether the geolocation time zone detection feature is enabled. Setting this to false means
+         the feature cannot be used. Setting this to true means it may be used if other
+         configuration allows (see provider configuration below, also compile time overlays). -->
     <bool name="config_enableGeolocationTimeZoneDetection" translatable="false">true</bool>
 
-    <!-- Whether the primary LocationTimeZoneProvider is enabled device.
+    <!-- Whether the primary LocationTimeZoneProvider is enabled.
          Ignored if config_enableGeolocationTimeZoneDetection is false -->
     <bool name="config_enablePrimaryLocationTimeZoneProvider" translatable="false">false</bool>
-    <!-- Used when enablePrimaryLocationTimeZoneProvider is true. Controls whether to enable primary
-         location time zone provider overlay which allows the primary location time zone provider to
-         be replaced by an app at run-time. When disabled, only the
-         config_primaryLocationTimeZoneProviderPackageName package will be searched for the primary
-         location time zone provider, otherwise any system package is eligible. Anyone who wants to
-         disable the runtime overlay mechanism can set it to false. -->
-    <bool name="config_enablePrimaryLocationTimeZoneOverlay" translatable="false">false</bool>
-    <!-- Package name providing the primary location time zone provider. Used only when
-         config_enablePrimaryLocationTimeZoneOverlay is false. -->
+    <!-- The package name providing the primary location time zone provider.
+         Only used when config_enableGeolocationTimeZoneDetection and
+         enablePrimaryLocationTimeZoneProvider are true. -->
     <string name="config_primaryLocationTimeZoneProviderPackageName" translatable="false">@null</string>
 
-    <!-- Whether the secondary LocationTimeZoneProvider is enabled device.
+    <!-- Whether the secondary LocationTimeZoneProvider is enabled.
          Ignored if config_enableGeolocationTimeZoneDetection is false -->
     <bool name="config_enableSecondaryLocationTimeZoneProvider" translatable="false">true</bool>
-    <!-- Used when enableSecondaryLocationTimeZoneProvider is true. Controls whether to enable
-         secondary location time zone provider overlay which allows the primary location time zone
-         provider to config_secondaryLocationTimeZoneProviderPackageName package will be searched
-         for the secondary location time zone provider, otherwise any system package is eligible.
-         Anyone who wants to disable the runtime overlay mechanism can set it to false. -->
-    <bool name="config_enableSecondaryLocationTimeZoneOverlay" translatable="false">false</bool>
     <!-- Package name providing the secondary location time zone provider. Used only when
          config_enableSecondaryLocationTimeZoneOverlay is false.
 
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index eb1fe1dd367d8..408620a13aad1 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -2180,10 +2180,8 @@
   <java-symbol type="bool" name="config_enableGnssTimeUpdateService" />
   <java-symbol type="bool" name="config_enableGeolocationTimeZoneDetection" />
   <java-symbol type="bool" name="config_enablePrimaryLocationTimeZoneProvider" />
-  <java-symbol type="bool" name="config_enablePrimaryLocationTimeZoneOverlay" />
   <java-symbol type="string" name="config_primaryLocationTimeZoneProviderPackageName" />
   <java-symbol type="bool" name="config_enableSecondaryLocationTimeZoneProvider" />
-  <java-symbol type="bool" name="config_enableSecondaryLocationTimeZoneOverlay" />
   <java-symbol type="string" name="config_secondaryLocationTimeZoneProviderPackageName" />
 
   <java-symbol type="layout" name="resolver_list" />
diff --git a/services/core/java/com/android/server/timedetector/ServerFlags.java b/services/core/java/com/android/server/timedetector/ServerFlags.java
index 52ff48b6a2775..d91e9c2585481 100644
--- a/services/core/java/com/android/server/timedetector/ServerFlags.java
+++ b/services/core/java/com/android/server/timedetector/ServerFlags.java
@@ -28,6 +28,8 @@ import com.android.internal.annotations.GuardedBy;
 import com.android.server.timezonedetector.ConfigurationChangeListener;
 import com.android.server.timezonedetector.ServiceConfigAccessor;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 import java.time.Duration;
 import java.util.Map;
 import java.util.Objects;
@@ -53,14 +55,15 @@ public final class ServerFlags {
      */
     @StringDef(prefix = "KEY_", value = {
             KEY_LOCATION_TIME_ZONE_DETECTION_FEATURE_SUPPORTED,
-            KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE,
-            KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE,
+            KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE,
+            KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE,
             KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_FUZZ_MILLIS,
             KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_MILLIS,
             KEY_LOCATION_TIME_ZONE_DETECTION_UNCERTAINTY_DELAY_MILLIS,
             KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_OVERRIDE,
             KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_DEFAULT,
     })
+    @Retention(RetentionPolicy.SOURCE)
     @interface DeviceConfigKey {}
 
     /**
@@ -75,19 +78,19 @@ public final class ServerFlags {
 
     /**
      * The key for the server flag that can override the device config for whether the primary
-     * location time zone provider is enabled or disabled.
+     * location time zone provider is enabled, disabled, or (for testing) in simulation mode.
      */
     @DeviceConfigKey
-    public static final String KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE =
-            "primary_location_time_zone_provider_enabled_override";
+    public static final String KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE =
+            "primary_location_time_zone_provider_mode_override";
 
     /**
      * The key for the server flag that can override the device config for whether the secondary
-     * location time zone provider is enabled or disabled.
+     * location time zone provider is enabled or disabled, or (for testing) in simulation mode.
      */
     @DeviceConfigKey
-    public static final String KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE =
-            "secondary_location_time_zone_provider_enabled_override";
+    public static final String KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE =
+            "secondary_location_time_zone_provider_mode_override";
 
     /**
      * The key for the minimum delay after location time zone detection has been enabled before the
@@ -195,6 +198,16 @@ public final class ServerFlags {
         }
     }
 
+    /**
+     * Returns an optional string value from {@link DeviceConfig} from the system_time
+     * namespace, returns {@link Optional#empty()} if there is no explicit value set.
+     */
+    @NonNull
+    public Optional<String> getOptionalString(@DeviceConfigKey String key) {
+        String value = DeviceConfig.getProperty(NAMESPACE_SYSTEM_TIME, key);
+        return Optional.ofNullable(value);
+    }
+
     /**
      * Returns an optional boolean value from {@link DeviceConfig} from the system_time
      * namespace, returns {@link Optional#empty()} if there is no explicit value set.
diff --git a/services/core/java/com/android/server/timezonedetector/ServiceConfigAccessor.java b/services/core/java/com/android/server/timezonedetector/ServiceConfigAccessor.java
index 222e852728f53..50d37f42e8890 100644
--- a/services/core/java/com/android/server/timezonedetector/ServiceConfigAccessor.java
+++ b/services/core/java/com/android/server/timezonedetector/ServiceConfigAccessor.java
@@ -17,6 +17,7 @@ package com.android.server.timezonedetector;
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
+import android.annotation.StringDef;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.content.res.Resources;
@@ -27,6 +28,10 @@ import com.android.internal.R;
 import com.android.internal.annotations.GuardedBy;
 import com.android.server.timedetector.ServerFlags;
 
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 import java.time.Duration;
 import java.util.Collections;
 import java.util.Objects;
@@ -40,13 +45,38 @@ import java.util.Set;
  */
 public final class ServiceConfigAccessor {
 
+    @StringDef(prefix = "PROVIDER_MODE_",
+            value = { PROVIDER_MODE_SIMULATED, PROVIDER_MODE_DISABLED, PROVIDER_MODE_ENABLED})
+    @Retention(RetentionPolicy.SOURCE)
+    @Target(ElementType.TYPE_USE)
+    @interface ProviderMode {}
+
+    /**
+     * The "simulated" provider mode.
+     * For use with {@link #getPrimaryLocationTimeZoneProviderMode()} and {@link
+     * #getSecondaryLocationTimeZoneProviderMode()}.
+     */
+    public static final @ProviderMode String PROVIDER_MODE_SIMULATED = "simulated";
+
+    /**
+     * The "disabled" provider mode. For use with {@link #getPrimaryLocationTimeZoneProviderMode()}
+     * and {@link #getSecondaryLocationTimeZoneProviderMode()}.
+     */
+    public static final @ProviderMode String PROVIDER_MODE_DISABLED = "disabled";
+
+    /**
+     * The "enabled" provider mode. For use with {@link #getPrimaryLocationTimeZoneProviderMode()}
+     * and {@link #getSecondaryLocationTimeZoneProviderMode()}.
+     */
+    public static final @ProviderMode String PROVIDER_MODE_ENABLED = "enabled";
+
     private static final Set<String> SERVER_FLAGS_KEYS_TO_WATCH = Collections.unmodifiableSet(
             new ArraySet<>(new String[] {
                     ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_FEATURE_SUPPORTED,
                     ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_DEFAULT,
                     ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_OVERRIDE,
-                    ServerFlags.KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE,
-                    ServerFlags.KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE,
+                    ServerFlags.KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE,
+                    ServerFlags.KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE,
                     ServerFlags.KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_MILLIS,
                     ServerFlags.KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_FUZZ_MILLIS,
                     ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_UNCERTAINTY_DELAY_MILLIS
@@ -139,14 +169,28 @@ public final class ServiceConfigAccessor {
 
     /**
      * Returns {@code true} if the location-based time zone detection feature is supported on the
-     * device. This can be used during feature testing on builds that are capable of location time
-     * zone detection to enable / disable the feature for some users.
+     * device.
      */
     public boolean isGeoTimeZoneDetectionFeatureSupported() {
+        // For the feature to be enabled it must:
+        // 1) Be turned on in config.
+        // 2) Not be turned off via a server flag.
+        // 3) There must be at least one location time zone provider enabled / configured.
         return mGeoDetectionFeatureSupportedInConfig
-                && isGeoTimeZoneDetectionFeatureSupportedInternal();
+                && isGeoTimeZoneDetectionFeatureSupportedInternal()
+                && atLeastOneProviderIsEnabled();
     }
 
+    private boolean atLeastOneProviderIsEnabled() {
+        return !(Objects.equals(getPrimaryLocationTimeZoneProviderMode(), PROVIDER_MODE_DISABLED)
+                && Objects.equals(getSecondaryLocationTimeZoneProviderMode(),
+                PROVIDER_MODE_DISABLED));
+    }
+
+    /**
+     * Returns {@code true} if the location-based time zone detection feature is not explicitly
+     * disabled by a server flag.
+     */
     private boolean isGeoTimeZoneDetectionFeatureSupportedInternal() {
         final boolean defaultEnabled = true;
         return mServerFlags.getBoolean(
@@ -154,42 +198,49 @@ public final class ServiceConfigAccessor {
                 defaultEnabled);
     }
 
+    @NonNull
+    public String getPrimaryLocationTimeZoneProviderPackageName() {
+        return mContext.getResources().getString(
+                R.string.config_primaryLocationTimeZoneProviderPackageName);
+    }
+
+    @NonNull
+    public String getSecondaryLocationTimeZoneProviderPackageName() {
+        return mContext.getResources().getString(
+                R.string.config_secondaryLocationTimeZoneProviderPackageName);
+    }
+
     /**
      * Returns {@code true} if the primary location time zone provider can be used.
      */
-    public boolean isPrimaryLocationTimeZoneProviderEnabled() {
-        return getPrimaryLocationTimeZoneProviderEnabledOverride()
-                .orElse(isPrimaryLocationTimeZoneProviderEnabledInConfig());
-    }
-
-    private boolean isPrimaryLocationTimeZoneProviderEnabledInConfig() {
-        int providerEnabledConfigId = R.bool.config_enablePrimaryLocationTimeZoneProvider;
-        return getConfigBoolean(providerEnabledConfigId);
+    @NonNull
+    public @ProviderMode String getPrimaryLocationTimeZoneProviderMode() {
+        return mServerFlags.getOptionalString(
+                ServerFlags.KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE)
+                .orElse(getPrimaryLocationTimeZoneProviderModeFromConfig());
     }
 
     @NonNull
-    private Optional<Boolean> getPrimaryLocationTimeZoneProviderEnabledOverride() {
-        return mServerFlags.getOptionalBoolean(
-                ServerFlags.KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE);
+    private @ProviderMode String getPrimaryLocationTimeZoneProviderModeFromConfig() {
+        int providerEnabledConfigId = R.bool.config_enablePrimaryLocationTimeZoneProvider;
+        return getConfigBoolean(providerEnabledConfigId)
+                ? PROVIDER_MODE_ENABLED : PROVIDER_MODE_DISABLED;
     }
 
     /**
-     * Returns {@code true} if the secondary location time zone provider can be used.
+     * Returns the mode for the secondary location time zone provider can be used.
      */
-    public boolean isSecondaryLocationTimeZoneProviderEnabled() {
-        return getSecondaryLocationTimeZoneProviderEnabledOverride()
-                .orElse(isSecondaryLocationTimeZoneProviderEnabledInConfig());
-    }
-
-    private boolean isSecondaryLocationTimeZoneProviderEnabledInConfig() {
-        int providerEnabledConfigId = R.bool.config_enableSecondaryLocationTimeZoneProvider;
-        return getConfigBoolean(providerEnabledConfigId);
+    public @ProviderMode String getSecondaryLocationTimeZoneProviderMode() {
+        return mServerFlags.getOptionalString(
+                ServerFlags.KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE)
+                .orElse(getSecondaryLocationTimeZoneProviderModeFromConfig());
     }
 
     @NonNull
-    private Optional<Boolean> getSecondaryLocationTimeZoneProviderEnabledOverride() {
-        return mServerFlags.getOptionalBoolean(
-                ServerFlags.KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_ENABLED_OVERRIDE);
+    private @ProviderMode String getSecondaryLocationTimeZoneProviderModeFromConfig() {
+        int providerEnabledConfigId = R.bool.config_enableSecondaryLocationTimeZoneProvider;
+        return getConfigBoolean(providerEnabledConfigId)
+                ? PROVIDER_MODE_ENABLED : PROVIDER_MODE_DISABLED;
     }
 
     /**
diff --git a/services/core/java/com/android/server/timezonedetector/location/ControllerImpl.java b/services/core/java/com/android/server/timezonedetector/location/ControllerImpl.java
index fb2a18493b7d5..d2190fdc5bead 100644
--- a/services/core/java/com/android/server/timezonedetector/location/ControllerImpl.java
+++ b/services/core/java/com/android/server/timezonedetector/location/ControllerImpl.java
@@ -30,6 +30,7 @@ import static com.android.server.timezonedetector.location.TimeZoneProviderEvent
 import static com.android.server.timezonedetector.location.TimeZoneProviderEvent.EVENT_TYPE_UNCERTAIN;
 
 import android.annotation.DurationMillisLong;
+import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.os.RemoteCallback;
@@ -604,14 +605,14 @@ class ControllerImpl extends LocationTimeZoneProviderController {
      * known provider, then the command is logged and discarded.
      */
     void handleProviderTestCommand(
-            @NonNull String providerName, @NonNull TestCommand testCommand,
+            @IntRange(from = 0, to = 1) int providerIndex, @NonNull TestCommand testCommand,
             @Nullable RemoteCallback callback) {
         mThreadingDomain.assertCurrentThread();
 
-        LocationTimeZoneProvider targetProvider = getLocationTimeZoneProvider(providerName);
+        LocationTimeZoneProvider targetProvider = getLocationTimeZoneProvider(providerIndex);
         if (targetProvider == null) {
             warnLog("Unable to process test command:"
-                    + " providerName=" + providerName + ", testCommand=" + testCommand);
+                    + " providerIndex=" + providerIndex + ", testCommand=" + testCommand);
             return;
         }
 
@@ -620,7 +621,7 @@ class ControllerImpl extends LocationTimeZoneProviderController {
                 targetProvider.handleTestCommand(testCommand, callback);
             } catch (Exception e) {
                 warnLog("Unable to process test command:"
-                        + " providerName=" + providerName + ", testCommand=" + testCommand, e);
+                        + " providerIndex=" + providerIndex + ", testCommand=" + testCommand, e);
             }
         }
     }
@@ -658,14 +659,15 @@ class ControllerImpl extends LocationTimeZoneProviderController {
     }
 
     @Nullable
-    private LocationTimeZoneProvider getLocationTimeZoneProvider(@NonNull String providerName) {
+    private LocationTimeZoneProvider getLocationTimeZoneProvider(
+            @IntRange(from = 0, to = 1) int providerIndex) {
         LocationTimeZoneProvider targetProvider;
-        if (Objects.equals(mPrimaryProvider.getName(), providerName)) {
+        if (providerIndex == 0) {
             targetProvider = mPrimaryProvider;
-        } else if (Objects.equals(mSecondaryProvider.getName(), providerName)) {
+        } else if (providerIndex == 1) {
             targetProvider = mSecondaryProvider;
         } else {
-            warnLog("Bad providerName=" + providerName);
+            warnLog("Bad providerIndex=" + providerIndex);
             targetProvider = null;
         }
         return targetProvider;
diff --git a/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerService.java b/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerService.java
index 326cfe7c32239..d8d44d47be624 100644
--- a/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerService.java
+++ b/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerService.java
@@ -16,13 +16,12 @@
 
 package com.android.server.timezonedetector.location;
 
-import static android.app.time.LocationTimeZoneManager.PRIMARY_PROVIDER_NAME;
-import static android.app.time.LocationTimeZoneManager.PROVIDER_MODE_OVERRIDE_DISABLED;
-import static android.app.time.LocationTimeZoneManager.PROVIDER_MODE_OVERRIDE_NONE;
-import static android.app.time.LocationTimeZoneManager.PROVIDER_MODE_OVERRIDE_SIMULATED;
-import static android.app.time.LocationTimeZoneManager.SECONDARY_PROVIDER_NAME;
 import static android.app.time.LocationTimeZoneManager.SERVICE_NAME;
 
+import static com.android.server.timezonedetector.ServiceConfigAccessor.PROVIDER_MODE_DISABLED;
+import static com.android.server.timezonedetector.ServiceConfigAccessor.PROVIDER_MODE_SIMULATED;
+
+import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.content.Context;
@@ -37,12 +36,12 @@ import android.util.IndentingPrintWriter;
 import android.util.Log;
 import android.util.Slog;
 
-import com.android.internal.R;
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.util.DumpUtils;
 import com.android.internal.util.Preconditions;
 import com.android.server.FgThread;
 import com.android.server.SystemService;
+import com.android.server.timezonedetector.Dumpable;
 import com.android.server.timezonedetector.ServiceConfigAccessor;
 import com.android.server.timezonedetector.TimeZoneDetectorInternal;
 import com.android.server.timezonedetector.location.LocationTimeZoneProvider.ProviderMetricsLogger;
@@ -131,11 +130,15 @@ public class LocationTimeZoneManagerService extends Binder {
 
     private static final String ATTRIBUTION_TAG = "LocationTimeZoneService";
 
-    private static final String PRIMARY_LOCATION_TIME_ZONE_SERVICE_ACTION =
-            TimeZoneProviderService.PRIMARY_LOCATION_TIME_ZONE_PROVIDER_SERVICE_INTERFACE;
-    private static final String SECONDARY_LOCATION_TIME_ZONE_SERVICE_ACTION =
-            TimeZoneProviderService.SECONDARY_LOCATION_TIME_ZONE_PROVIDER_SERVICE_INTERFACE;
+    @GuardedBy("mSharedLock")
+    private final ProviderConfig mPrimaryProviderConfig = new ProviderConfig(
+            0 /* index */, "primary",
+            TimeZoneProviderService.PRIMARY_LOCATION_TIME_ZONE_PROVIDER_SERVICE_INTERFACE);
 
+    @GuardedBy("mSharedLock")
+    private final ProviderConfig mSecondaryProviderConfig = new ProviderConfig(
+            1 /* index */, "secondary",
+            TimeZoneProviderService.SECONDARY_LOCATION_TIME_ZONE_PROVIDER_SERVICE_INTERFACE);
 
     @NonNull private final Context mContext;
 
@@ -165,14 +168,6 @@ public class LocationTimeZoneManagerService extends Binder {
     @GuardedBy("mSharedLock")
     private ControllerEnvironmentImpl mEnvironment;
 
-    @GuardedBy("mSharedLock")
-    @NonNull
-    private String mPrimaryProviderModeOverride = PROVIDER_MODE_OVERRIDE_NONE;
-
-    @GuardedBy("mSharedLock")
-    @NonNull
-    private String mSecondaryProviderModeOverride = PROVIDER_MODE_OVERRIDE_NONE;
-
     LocationTimeZoneManagerService(Context context) {
         mContext = context.createAttributionContext(ATTRIBUTION_TAG);
         mHandler = FgThread.getHandler();
@@ -200,9 +195,14 @@ public class LocationTimeZoneManagerService extends Binder {
         mThreadingDomain.assertCurrentThread();
 
         synchronized (mSharedLock) {
-            // Stop and start the service, waiting until completion.
-            stopOnDomainThread();
-            startOnDomainThread();
+            // Avoid starting the service if it is currently stopped. This is required because
+            // server flags are used by tests to set behavior with the service stopped, and we don't
+            // want the service being restarted after each flag is set.
+            if (mLocationTimeZoneDetectorController != null) {
+                // Stop and start the service, waiting until completion.
+                stopOnDomainThread();
+                startOnDomainThread();
+            }
         }
     }
 
@@ -257,8 +257,8 @@ public class LocationTimeZoneManagerService extends Binder {
             }
 
             if (mLocationTimeZoneDetectorController == null) {
-                LocationTimeZoneProvider primary = createPrimaryProvider();
-                LocationTimeZoneProvider secondary = createSecondaryProvider();
+                LocationTimeZoneProvider primary = mPrimaryProviderConfig.createProvider();
+                LocationTimeZoneProvider secondary = mSecondaryProviderConfig.createProvider();
 
                 ControllerImpl controller =
                         new ControllerImpl(mThreadingDomain, primary, secondary);
@@ -273,88 +273,6 @@ public class LocationTimeZoneManagerService extends Binder {
         }
     }
 
-    @NonNull
-    private LocationTimeZoneProvider createPrimaryProvider() {
-        LocationTimeZoneProviderProxy proxy;
-        if (isProviderInSimulationMode(PRIMARY_PROVIDER_NAME)) {
-            proxy = new SimulatedLocationTimeZoneProviderProxy(mContext, mThreadingDomain);
-        } else if (!isProviderEnabled(PRIMARY_PROVIDER_NAME)) {
-            proxy = new NullLocationTimeZoneProviderProxy(mContext, mThreadingDomain);
-        } else {
-            proxy = new RealLocationTimeZoneProviderProxy(
-                    mContext,
-                    mHandler,
-                    mThreadingDomain,
-                    PRIMARY_LOCATION_TIME_ZONE_SERVICE_ACTION,
-                    R.bool.config_enablePrimaryLocationTimeZoneOverlay,
-                    R.string.config_primaryLocationTimeZoneProviderPackageName
-            );
-        }
-        ProviderMetricsLogger providerMetricsLogger = new RealProviderMetricsLogger(0);
-        return new BinderLocationTimeZoneProvider(
-                providerMetricsLogger, mThreadingDomain, PRIMARY_PROVIDER_NAME, proxy);
-    }
-
-    @NonNull
-    private LocationTimeZoneProvider createSecondaryProvider() {
-        LocationTimeZoneProviderProxy proxy;
-        if (isProviderInSimulationMode(SECONDARY_PROVIDER_NAME)) {
-            proxy = new SimulatedLocationTimeZoneProviderProxy(mContext, mThreadingDomain);
-        } else if (!isProviderEnabled(SECONDARY_PROVIDER_NAME)) {
-            proxy = new NullLocationTimeZoneProviderProxy(mContext, mThreadingDomain);
-        } else {
-            proxy = new RealLocationTimeZoneProviderProxy(
-                    mContext,
-                    mHandler,
-                    mThreadingDomain,
-                    SECONDARY_LOCATION_TIME_ZONE_SERVICE_ACTION,
-                    R.bool.config_enableSecondaryLocationTimeZoneOverlay,
-                    R.string.config_secondaryLocationTimeZoneProviderPackageName
-            );
-        }
-        ProviderMetricsLogger providerMetricsLogger = new RealProviderMetricsLogger(1);
-        return new BinderLocationTimeZoneProvider(
-                providerMetricsLogger, mThreadingDomain, SECONDARY_PROVIDER_NAME, proxy);
-    }
-
-    /** Used for bug triage and in tests to simulate provider events. */
-    private boolean isProviderInSimulationMode(@NonNull String providerName) {
-        return isProviderModeOverrideSet(providerName, PROVIDER_MODE_OVERRIDE_SIMULATED);
-    }
-
-    /** Used for bug triage, and by tests and experiments to remove a provider. */
-    private boolean isProviderEnabled(@NonNull String providerName) {
-        if (isProviderModeOverrideSet(providerName, PROVIDER_MODE_OVERRIDE_DISABLED)) {
-            return false;
-        }
-
-        switch (providerName) {
-            case PRIMARY_PROVIDER_NAME: {
-                return mServiceConfigAccessor.isPrimaryLocationTimeZoneProviderEnabled();
-            }
-            case SECONDARY_PROVIDER_NAME: {
-                return mServiceConfigAccessor.isSecondaryLocationTimeZoneProviderEnabled();
-            }
-            default: {
-                throw new IllegalArgumentException(providerName);
-            }
-        }
-    }
-
-    private boolean isProviderModeOverrideSet(@NonNull String providerName, @NonNull String mode) {
-        switch (providerName) {
-            case PRIMARY_PROVIDER_NAME: {
-                return Objects.equals(mPrimaryProviderModeOverride, mode);
-            }
-            case SECONDARY_PROVIDER_NAME: {
-                return Objects.equals(mSecondaryProviderModeOverride, mode);
-            }
-            default: {
-                throw new IllegalArgumentException(providerName);
-            }
-        }
-    }
-
     /**
      * Stops the service for tests and other rare cases. To avoid tests needing to sleep, this
      * method will not return until all the system server components have stopped.
@@ -389,33 +307,6 @@ public class LocationTimeZoneManagerService extends Binder {
                 this, in, out, err, args, callback, resultReceiver);
     }
 
-    /** Sets this service into provider state recording mode for tests. */
-    void setProviderModeOverride(@NonNull String providerName, @NonNull String mode) {
-        enforceManageTimeZoneDetectorPermission();
-
-        Preconditions.checkArgument(
-                PRIMARY_PROVIDER_NAME.equals(providerName)
-                        || SECONDARY_PROVIDER_NAME.equals(providerName));
-        Preconditions.checkArgument(PROVIDER_MODE_OVERRIDE_DISABLED.equals(mode)
-                || PROVIDER_MODE_OVERRIDE_SIMULATED.equals(mode)
-                || PROVIDER_MODE_OVERRIDE_NONE.equals(mode));
-
-        mThreadingDomain.postAndWait(() -> {
-            synchronized (mSharedLock) {
-                switch (providerName) {
-                    case PRIMARY_PROVIDER_NAME: {
-                        mPrimaryProviderModeOverride = mode;
-                        break;
-                    }
-                    case SECONDARY_PROVIDER_NAME: {
-                        mSecondaryProviderModeOverride = mode;
-                        break;
-                    }
-                }
-            }
-        }, BLOCKING_OP_WAIT_DURATION_MILLIS);
-    }
-
     /** Sets this service into provider state recording mode for tests. */
     void setProviderStateRecordingEnabled(boolean enabled) {
         enforceManageTimeZoneDetectorPermission();
@@ -457,8 +348,8 @@ public class LocationTimeZoneManagerService extends Binder {
      * Passes a {@link TestCommand} to the specified provider and waits for the response.
      */
     @NonNull
-    Bundle handleProviderTestCommand(
-            @NonNull String providerName, @NonNull TestCommand testCommand) {
+    Bundle handleProviderTestCommand(@IntRange(from = 0, to = 1) int providerIndex,
+            @NonNull TestCommand testCommand) {
         enforceManageTimeZoneDetectorPermission();
 
         // Because this method blocks and posts work to the threading domain thread, it would cause
@@ -479,7 +370,7 @@ public class LocationTimeZoneManagerService extends Binder {
                     return;
                 }
                 mLocationTimeZoneDetectorController.handleProviderTestCommand(
-                        providerName, testCommand, remoteCallback);
+                        providerIndex, testCommand, remoteCallback);
             }
         });
 
@@ -505,6 +396,17 @@ public class LocationTimeZoneManagerService extends Binder {
         synchronized (mSharedLock) {
             ipw.println("LocationTimeZoneManagerService:");
             ipw.increaseIndent();
+
+            ipw.println("Primary provider config:");
+            ipw.increaseIndent();
+            mPrimaryProviderConfig.dump(ipw, args);
+            ipw.decreaseIndent();
+
+            ipw.println("Secondary provider config:");
+            ipw.increaseIndent();
+            mSecondaryProviderConfig.dump(ipw, args);
+            ipw.decreaseIndent();
+
             if (mLocationTimeZoneDetectorController == null) {
                 ipw.println("{Stopped}");
             } else {
@@ -541,4 +443,75 @@ public class LocationTimeZoneManagerService extends Binder {
                 android.Manifest.permission.MANAGE_TIME_AND_ZONE_DETECTION,
                 "manage time and time zone detection");
     }
+
+    /** An inner class for managing a provider's config. */
+    private final class ProviderConfig implements Dumpable {
+        @IntRange(from = 0, to = 1) private final int mIndex;
+        @NonNull private final String mName;
+        @NonNull private final String mServiceAction;
+
+        ProviderConfig(@IntRange(from = 0, to = 1) int index, @NonNull String name,
+                @NonNull String serviceAction) {
+            Preconditions.checkArgument(index >= 0 && index <= 1);
+            mIndex = index;
+            mName = Objects.requireNonNull(name);
+            mServiceAction = Objects.requireNonNull(serviceAction);
+        }
+
+        @NonNull
+        LocationTimeZoneProvider createProvider() {
+            LocationTimeZoneProviderProxy proxy = createProxy();
+            ProviderMetricsLogger providerMetricsLogger = new RealProviderMetricsLogger(mIndex);
+            return new BinderLocationTimeZoneProvider(
+                    providerMetricsLogger, mThreadingDomain, mName, proxy);
+        }
+
+        @GuardedBy("mSharedLock")
+        @Override
+        public void dump(IndentingPrintWriter ipw, String[] args) {
+            ipw.printf("getMode()=%s\n", getMode());
+            ipw.printf("getPackageName()=%s\n", getPackageName());
+        }
+
+        @NonNull
+        private LocationTimeZoneProviderProxy createProxy() {
+            String mode = getMode();
+            if (Objects.equals(mode, PROVIDER_MODE_SIMULATED)) {
+                return new SimulatedLocationTimeZoneProviderProxy(mContext, mThreadingDomain);
+            } else if (Objects.equals(mode, PROVIDER_MODE_DISABLED)) {
+                return new NullLocationTimeZoneProviderProxy(mContext, mThreadingDomain);
+            } else {
+                // mode == PROVIDER_MODE_OVERRIDE_ENABLED (or unknown).
+                return createRealProxy();
+            }
+        }
+
+        /** Returns the mode of the provider. */
+        @NonNull
+        private String getMode() {
+            if (mIndex == 0) {
+                return mServiceConfigAccessor.getPrimaryLocationTimeZoneProviderMode();
+            } else {
+                return mServiceConfigAccessor.getSecondaryLocationTimeZoneProviderMode();
+            }
+        }
+
+        @NonNull
+        private RealLocationTimeZoneProviderProxy createRealProxy() {
+            String providerServiceAction = mServiceAction;
+            String providerPackageName = getPackageName();
+            return new RealLocationTimeZoneProviderProxy(
+                    mContext, mHandler, mThreadingDomain, providerServiceAction,
+                    providerPackageName);
+        }
+
+        @NonNull
+        private String getPackageName() {
+            if (mIndex == 0) {
+                return mServiceConfigAccessor.getPrimaryLocationTimeZoneProviderPackageName();
+            } else {
+                return mServiceConfigAccessor.getSecondaryLocationTimeZoneProviderPackageName();
+            }
+        }
+    }
 }
diff --git a/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerShellCommand.java b/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerShellCommand.java
index 40638080004c5..c6df6241bf21b 100644
--- a/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerShellCommand.java
+++ b/services/core/java/com/android/server/timezonedetector/location/LocationTimeZoneManagerShellCommand.java
@@ -16,19 +16,25 @@
 package com.android.server.timezonedetector.location;
 
 import static android.app.time.LocationTimeZoneManager.DUMP_STATE_OPTION_PROTO;
-import static android.app.time.LocationTimeZoneManager.PRIMARY_PROVIDER_NAME;
-import static android.app.time.LocationTimeZoneManager.PROVIDER_MODE_OVERRIDE_DISABLED;
-import static android.app.time.LocationTimeZoneManager.PROVIDER_MODE_OVERRIDE_NONE;
-import static android.app.time.LocationTimeZoneManager.PROVIDER_MODE_OVERRIDE_SIMULATED;
-import static android.app.time.LocationTimeZoneManager.SECONDARY_PROVIDER_NAME;
 import static android.app.time.LocationTimeZoneManager.SERVICE_NAME;
 import static android.app.time.LocationTimeZoneManager.SHELL_COMMAND_DUMP_STATE;
 import static android.app.time.LocationTimeZoneManager.SHELL_COMMAND_RECORD_PROVIDER_STATES;
 import static android.app.time.LocationTimeZoneManager.SHELL_COMMAND_SEND_PROVIDER_TEST_COMMAND;
-import static android.app.time.LocationTimeZoneManager.SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE;
 import static android.app.time.LocationTimeZoneManager.SHELL_COMMAND_START;
 import static android.app.time.LocationTimeZoneManager.SHELL_COMMAND_STOP;
+import static android.provider.DeviceConfig.NAMESPACE_SYSTEM_TIME;
 
+import static com.android.server.timedetector.ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_FEATURE_SUPPORTED;
+import static com.android.server.timedetector.ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_DEFAULT;
+import static com.android.server.timedetector.ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_OVERRIDE;
+import static com.android.server.timedetector.ServerFlags.KEY_LOCATION_TIME_ZONE_DETECTION_UNCERTAINTY_DELAY_MILLIS;
+import static com.android.server.timedetector.ServerFlags.KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_FUZZ_MILLIS;
+import static com.android.server.timedetector.ServerFlags.KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_MILLIS;
+import static com.android.server.timedetector.ServerFlags.KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE;
+import static com.android.server.timedetector.ServerFlags.KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE;
+import static com.android.server.timezonedetector.ServiceConfigAccessor.PROVIDER_MODE_DISABLED;
+import static com.android.server.timezonedetector.ServiceConfigAccessor.PROVIDER_MODE_ENABLED;
+import static com.android.server.timezonedetector.ServiceConfigAccessor.PROVIDER_MODE_SIMULATED;
 import static com.android.server.timezonedetector.location.LocationTimeZoneProvider.ProviderState.PROVIDER_STATE_DESTROYED;
 import static com.android.server.timezonedetector.location.LocationTimeZoneProvider.ProviderState.PROVIDER_STATE_PERM_FAILED;
 import static com.android.server.timezonedetector.location.LocationTimeZoneProvider.ProviderState.PROVIDER_STATE_STARTED_CERTAIN;
@@ -53,16 +59,12 @@ import com.android.server.timezonedetector.location.LocationTimeZoneProvider.Pro
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
-import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
 
 /** Implements the shell command interface for {@link LocationTimeZoneManagerService}. */
 class LocationTimeZoneManagerShellCommand extends ShellCommand {
 
-    private static final List<String> VALID_PROVIDER_NAMES =
-            Arrays.asList(PRIMARY_PROVIDER_NAME, SECONDARY_PROVIDER_NAME);
-
     private final LocationTimeZoneManagerService mService;
 
     LocationTimeZoneManagerShellCommand(LocationTimeZoneManagerService service) {
@@ -82,9 +84,6 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
             case SHELL_COMMAND_STOP: {
                 return runStop();
             }
-            case SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE: {
-                return runSetProviderModeOverride();
-            }
             case SHELL_COMMAND_SEND_PROVIDER_TEST_COMMAND: {
                 return runSendProviderTestCommand();
             }
@@ -110,10 +109,6 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
         pw.println("    Starts the location_time_zone_manager, creating time zone providers.");
         pw.printf("  %s\n", SHELL_COMMAND_STOP);
         pw.println("    Stops the location_time_zone_manager, destroying time zone providers.");
-        pw.printf("  %s <provider name> <mode>\n", SHELL_COMMAND_SET_PROVIDER_MODE_OVERRIDE);
-        pw.println("    Sets a provider into a test mode next time the service started.");
-        pw.printf("    Values: %s|%s|%s\n", PROVIDER_MODE_OVERRIDE_NONE,
-                PROVIDER_MODE_OVERRIDE_DISABLED, PROVIDER_MODE_OVERRIDE_SIMULATED);
         pw.printf("  %s (true|false)\n", SHELL_COMMAND_RECORD_PROVIDER_STATES);
         pw.printf("    Enables / disables provider state recording mode. See also %s. The default"
                 + " state is always \"false\".\n", SHELL_COMMAND_DUMP_STATE);
@@ -126,11 +121,11 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
         pw.println("    Dumps Location Time Zone Manager state for tests as text or binary proto"
                 + " form.");
         pw.println("    See the LocationTimeZoneManagerServiceStateProto definition for details.");
-        pw.printf("  %s <provider name> <test command>\n",
+        pw.printf("  %s <provider index> <test command>\n",
                 SHELL_COMMAND_SEND_PROVIDER_TEST_COMMAND);
         pw.println("    Passes a test command to the named provider.");
         pw.println();
-        pw.printf("<provider name> = One of %s\n", VALID_PROVIDER_NAMES);
+        pw.println("<provider index> = 0 (primary), 1 (secondary)");
         pw.println();
         pw.printf("%s details:\n", SHELL_COMMAND_SEND_PROVIDER_TEST_COMMAND);
         pw.println();
@@ -146,6 +141,47 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
         pw.println();
         pw.println("Test commands cannot currently be passed to real provider implementations.");
         pw.println();
+        pw.printf("This service is also affected by the following device_config flags in the"
+                + " %s namespace:\n", NAMESPACE_SYSTEM_TIME);
+        pw.printf("    %s - [default=true], only observed if the feature is enabled in config,"
+                        + "set this to false to disable the feature\n",
+                KEY_LOCATION_TIME_ZONE_DETECTION_FEATURE_SUPPORTED);
+        pw.printf("    %s - [default=false]. Only used if the device does not have an explicit"
+                        + " 'location time zone detection enabled' setting configured [*].\n",
+                KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_DEFAULT);
+        pw.printf("    %s - [default=<unset>]. Used to override the device's 'location time zone"
+                        + " detection enabled' setting [*]\n",
+                KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_OVERRIDE);
+        pw.printf("    %s - Overrides the mode of the primary provider. Values=%s|%s|%s\n",
+                KEY_PRIMARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE,
+                PROVIDER_MODE_DISABLED, PROVIDER_MODE_ENABLED, PROVIDER_MODE_SIMULATED);
+        pw.printf("    %s - Overrides the mode of the secondary provider. Values=%s|%s|%s\n",
+                KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE,
+                PROVIDER_MODE_DISABLED, PROVIDER_MODE_ENABLED, PROVIDER_MODE_SIMULATED);
+        pw.printf("    %s - \n",
+                KEY_SECONDARY_LOCATION_TIME_ZONE_PROVIDER_MODE_OVERRIDE);
+        pw.printf("    %s - Sets the amount of time the service waits when uncertain before making"
+                        + " an 'uncertain' suggestion to the time zone detector.\n",
+                KEY_LOCATION_TIME_ZONE_DETECTION_UNCERTAINTY_DELAY_MILLIS);
+        pw.printf("    %s - Sets the initialization time passed to the location time zone providers"
+                        + "\n",
+                KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_MILLIS);
+        pw.printf("    %s - Sets the amount of extra time added to the location time zone providers"
+                        + " initialization time\n",
+                KEY_LOCATION_TIME_ZONE_PROVIDER_INITIALIZATION_TIMEOUT_FUZZ_MILLIS);
+        pw.println();
+        pw.println("[*] The user must still have location = on / auto time zone detection = on");
+        pw.println();
+        pw.printf("Typically, use '%s' to stop the service before setting individual"
+                + " flags and '%s' after to restart it.\n",
+                SHELL_COMMAND_STOP, SHELL_COMMAND_START);
+        pw.println();
+        pw.println("Example:");
+        pw.printf("    $ adb shell cmd device_config put %s %s %s\n",
+                NAMESPACE_SYSTEM_TIME, KEY_LOCATION_TIME_ZONE_DETECTION_SETTING_ENABLED_DEFAULT,
+                "true");
+        pw.println("See adb shell cmd device_config for more information.");
+        pw.println();
     }
 
     private int runStart() {
@@ -172,21 +208,6 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
         return 0;
     }
 
-    private int runSetProviderModeOverride() {
-        PrintWriter outPrintWriter = getOutPrintWriter();
-        try {
-            String providerName = getNextArgRequired();
-            String modeOverride = getNextArgRequired();
-            outPrintWriter.println("Setting provider mode override for " + providerName
-                    + " to " + modeOverride);
-            mService.setProviderModeOverride(providerName, modeOverride);
-        } catch (RuntimeException e) {
-            reportError(e);
-            return 1;
-        }
-        return 0;
-    }
-
     private int runRecordProviderStates() {
         PrintWriter outPrintWriter = getOutPrintWriter();
         boolean enabled;
@@ -293,10 +314,10 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
     private int runSendProviderTestCommand() {
         PrintWriter outPrintWriter = getOutPrintWriter();
 
-        String providerName;
+        int providerIndex;
         TestCommand testCommand;
         try {
-            providerName = validateProviderName(getNextArgRequired());
+            providerIndex = parseProviderIndex(getNextArgRequired());
             testCommand = createTestCommandFromNextShellArg();
         } catch (RuntimeException e) {
             reportError(e);
@@ -304,9 +325,9 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
         }
 
         outPrintWriter.println("Injecting testCommand=" + testCommand
-                + " to providerName=" + providerName);
+                + " to providerIndex=" + providerIndex);
         try {
-            Bundle result = mService.handleProviderTestCommand(providerName, testCommand);
+            Bundle result = mService.handleProviderTestCommand(providerIndex, testCommand);
             outPrintWriter.println(result);
         } catch (RuntimeException e) {
             reportError(e);
@@ -326,11 +347,11 @@ class LocationTimeZoneManagerShellCommand extends ShellCommand {
         e.printStackTrace(errPrintWriter);
     }
 
-    @NonNull
-    static String validateProviderName(@NonNull String value) {
-        if (!VALID_PROVIDER_NAMES.contains(value)) {
-            throw new IllegalArgumentException("Unknown provider name=" + value);
+    private static int parseProviderIndex(@NonNull String providerIndexString) {
+        int providerIndex = Integer.parseInt(providerIndexString);
+        if (providerIndex < 0 || providerIndex > 1) {
+            throw new IllegalArgumentException(providerIndexString);
         }
-        return value;
+        return providerIndex;
     }
 }
diff --git a/services/core/java/com/android/server/timezonedetector/location/RealLocationTimeZoneProviderProxy.java b/services/core/java/com/android/server/timezonedetector/location/RealLocationTimeZoneProviderProxy.java
index 6c3f016588f81..b5ac712a35229 100644
--- a/services/core/java/com/android/server/timezonedetector/location/RealLocationTimeZoneProviderProxy.java
+++ b/services/core/java/com/android/server/timezonedetector/location/RealLocationTimeZoneProviderProxy.java
@@ -62,15 +62,17 @@ class RealLocationTimeZoneProviderProxy extends LocationTimeZoneProviderProxy im
     RealLocationTimeZoneProviderProxy(
             @NonNull Context context, @NonNull Handler handler,
             @NonNull ThreadingDomain threadingDomain, @NonNull String action,
-            int enableOverlayResId, int nonOverlayPackageResId) {
+            @NonNull String providerPackageName) {
         super(context, threadingDomain);
         mManagerProxy = null;
         mRequest = TimeZoneProviderRequest.createStopUpdatesRequest();
+
+        Objects.requireNonNull(providerPackageName);
         mServiceWatcher = ServiceWatcher.create(context,
                 handler,
                 "RealLocationTimeZoneProviderProxy",
-                new CurrentUserServiceSupplier(context, action, enableOverlayResId,
-                        nonOverlayPackageResId, BIND_TIME_ZONE_PROVIDER_SERVICE,
+                new CurrentUserServiceSupplier(context, action,
+                        providerPackageName, BIND_TIME_ZONE_PROVIDER_SERVICE,
                         INSTALL_LOCATION_TIME_ZONE_PROVIDER_SERVICE),
                 this);
     }