diff --git a/api/system-current.txt b/api/system-current.txt
index b187a783882ef..d003945cecee5 100755
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -313,12 +313,10 @@ package android.app {
     method @NonNull public java.util.Collection<java.util.Locale> getSupportedLocales();
     method @RequiresPermission(android.Manifest.permission.PACKAGE_USAGE_STATS) public int getUidImportance(int);
     method @RequiresPermission(android.Manifest.permission.KILL_UID) public void killUid(int, String);
-    method public void registerHomeVisibilityObserver(@NonNull android.app.HomeVisibilityObserver);
     method @RequiresPermission(android.Manifest.permission.PACKAGE_USAGE_STATS) public void removeOnUidImportanceListener(android.app.ActivityManager.OnUidImportanceListener);
     method public void setDeviceLocales(@NonNull android.os.LocaleList);
     method @RequiresPermission(android.Manifest.permission.RESTRICTED_VR_ACCESS) public static void setPersistentVrThread(int);
     method @RequiresPermission(android.Manifest.permission.MANAGE_USERS) public boolean switchUser(@NonNull android.os.UserHandle);
-    method public void unregisterHomeVisibilityObserver(@NonNull android.app.HomeVisibilityObserver);
   }
 
   public static interface ActivityManager.OnUidImportanceListener {
@@ -505,11 +503,6 @@ package android.app {
     field public static final String ACTION_DOWNLOAD_COMPLETED = "android.intent.action.DOWNLOAD_COMPLETED";
   }
 
-  public abstract class HomeVisibilityObserver {
-    ctor public HomeVisibilityObserver();
-    method public abstract void onHomeVisibilityChanged(boolean);
-  }
-
   public abstract class InstantAppResolverService extends android.app.Service {
     ctor public InstantAppResolverService();
     method public final void attachBaseContext(android.content.Context);
@@ -9155,7 +9148,6 @@ package android.telephony {
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public boolean rebootRadio();
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void reportDefaultNetworkStatus(boolean);
     method @RequiresPermission(allOf={android.Manifest.permission.ACCESS_FINE_LOCATION, android.Manifest.permission.MODIFY_PHONE_STATE}) public void requestCellInfoUpdate(@NonNull android.os.WorkSource, @NonNull java.util.concurrent.Executor, @NonNull android.telephony.TelephonyManager.CellInfoCallback);
-    method public void requestModemActivityInfo(@NonNull android.os.ResultReceiver);
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void requestNumberVerification(@NonNull android.telephony.PhoneNumberRange, long, @NonNull java.util.concurrent.Executor, @NonNull android.telephony.NumberVerificationCallback);
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void resetAllCarrierActions();
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void resetCarrierKeysForImsiEncryption();
@@ -9217,12 +9209,6 @@ package android.telephony {
     field public static final String EXTRA_APN_TYPE_INT = "apnTypeInt";
     field public static final String EXTRA_DATA_SPN = "android.telephony.extra.DATA_SPN";
     field public static final String EXTRA_DEFAULT_NETWORK_AVAILABLE = "defaultNetworkAvailable";
-    field public static final String EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE = "android.telephony.extra.DEFAULT_SUBSCRIPTION_SELECT_TYPE";
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_ALL = 4; // 0x4
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_DATA = 1; // 0x1
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_NONE = 0; // 0x0
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_SMS = 3; // 0x3
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_VOICE = 2; // 0x2
     field public static final String EXTRA_ERROR_CODE = "errorCode";
     field public static final String EXTRA_PCO_ID = "pcoId";
     field public static final String EXTRA_PCO_VALUE = "pcoValue";
@@ -9232,10 +9218,6 @@ package android.telephony {
     field public static final String EXTRA_REDIRECTION_URL = "redirectionUrl";
     field public static final String EXTRA_SHOW_PLMN = "android.telephony.extra.SHOW_PLMN";
     field public static final String EXTRA_SHOW_SPN = "android.telephony.extra.SHOW_SPN";
-    field public static final String EXTRA_SIM_COMBINATION_NAMES = "android.telephony.extra.SIM_COMBINATION_NAMES";
-    field public static final String EXTRA_SIM_COMBINATION_WARNING_TYPE = "android.telephony.extra.SIM_COMBINATION_WARNING_TYPE";
-    field public static final int EXTRA_SIM_COMBINATION_WARNING_TYPE_DUAL_CDMA = 1; // 0x1
-    field public static final int EXTRA_SIM_COMBINATION_WARNING_TYPE_NONE = 0; // 0x0
     field public static final String EXTRA_SIM_STATE = "android.telephony.extra.SIM_STATE";
     field public static final String EXTRA_SPN = "android.telephony.extra.SPN";
     field public static final String EXTRA_VISUAL_VOICEMAIL_ENABLED_BY_USER_BOOL = "android.telephony.extra.VISUAL_VOICEMAIL_ENABLED_BY_USER_BOOL";
@@ -9243,7 +9225,6 @@ package android.telephony {
     field public static final int INVALID_EMERGENCY_NUMBER_DB_VERSION = -1; // 0xffffffff
     field public static final int KEY_TYPE_EPDG = 1; // 0x1
     field public static final int KEY_TYPE_WLAN = 2; // 0x2
-    field public static final String MODEM_ACTIVITY_RESULT_KEY = "controller_activity";
     field public static final long NETWORK_TYPE_BITMASK_1xRTT = 64L; // 0x40L
     field public static final long NETWORK_TYPE_BITMASK_CDMA = 8L; // 0x8L
     field public static final long NETWORK_TYPE_BITMASK_EDGE = 2L; // 0x2L
diff --git a/core/java/android/app/ActivityManager.java b/core/java/android/app/ActivityManager.java
index 9d63bc2ef85a8..bdaa440345657 100644
--- a/core/java/android/app/ActivityManager.java
+++ b/core/java/android/app/ActivityManager.java
@@ -4356,9 +4356,9 @@ public class ActivityManager {
 
     /**
      * Register with {@link HomeVisibilityObserver} with ActivityManager.
+     * TODO: b/144351078 expose as SystemApi
      * @hide
      */
-    @SystemApi
     public void registerHomeVisibilityObserver(@NonNull HomeVisibilityObserver observer) {
         Preconditions.checkNotNull(observer);
         try {
@@ -4373,9 +4373,9 @@ public class ActivityManager {
 
     /**
      * Unregister with {@link HomeVisibilityObserver} with ActivityManager.
+     * TODO: b/144351078 expose as SystemApi
      * @hide
      */
-    @SystemApi
     public void unregisterHomeVisibilityObserver(@NonNull HomeVisibilityObserver observer) {
         Preconditions.checkNotNull(observer);
         try {
diff --git a/core/java/android/app/HomeVisibilityObserver.java b/core/java/android/app/HomeVisibilityObserver.java
index f3465f839b3b5..8422c6f6f8729 100644
--- a/core/java/android/app/HomeVisibilityObserver.java
+++ b/core/java/android/app/HomeVisibilityObserver.java
@@ -16,7 +16,6 @@
 
 package android.app;
 
-import android.annotation.SystemApi;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
@@ -28,9 +27,9 @@ import java.util.List;
  * An observer / callback to create and register by
  * {@link ActivityManager#registerHomeVisibilityObserver} so that it's triggered when
  * visibility of home page changes.
+ * TODO: b/144351078 expose as SystemApi
  * @hide
  */
-@SystemApi
 public abstract class HomeVisibilityObserver {
     private Context mContext;
     private ActivityManager mActivityManager;
diff --git a/telephony/api/system-current.txt b/telephony/api/system-current.txt
index a5514adb4e35c..874b7033f59d0 100644
--- a/telephony/api/system-current.txt
+++ b/telephony/api/system-current.txt
@@ -829,7 +829,6 @@ package android.telephony {
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public boolean rebootRadio();
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void reportDefaultNetworkStatus(boolean);
     method @RequiresPermission(allOf={android.Manifest.permission.ACCESS_FINE_LOCATION, android.Manifest.permission.MODIFY_PHONE_STATE}) public void requestCellInfoUpdate(@NonNull android.os.WorkSource, @NonNull java.util.concurrent.Executor, @NonNull android.telephony.TelephonyManager.CellInfoCallback);
-    method public void requestModemActivityInfo(@NonNull android.os.ResultReceiver);
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void requestNumberVerification(@NonNull android.telephony.PhoneNumberRange, long, @NonNull java.util.concurrent.Executor, @NonNull android.telephony.NumberVerificationCallback);
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void resetAllCarrierActions();
     method @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE) public void resetCarrierKeysForImsiEncryption();
@@ -898,12 +897,6 @@ package android.telephony {
     field public static final String EXTRA_APN_TYPE_INT = "apnTypeInt";
     field public static final String EXTRA_DATA_SPN = "android.telephony.extra.DATA_SPN";
     field public static final String EXTRA_DEFAULT_NETWORK_AVAILABLE = "defaultNetworkAvailable";
-    field public static final String EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE = "android.telephony.extra.DEFAULT_SUBSCRIPTION_SELECT_TYPE";
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_ALL = 4; // 0x4
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_DATA = 1; // 0x1
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_NONE = 0; // 0x0
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_SMS = 3; // 0x3
-    field public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_VOICE = 2; // 0x2
     field public static final String EXTRA_ERROR_CODE = "errorCode";
     field public static final String EXTRA_PCO_ID = "pcoId";
     field public static final String EXTRA_PCO_VALUE = "pcoValue";
@@ -913,10 +906,6 @@ package android.telephony {
     field public static final String EXTRA_REDIRECTION_URL = "redirectionUrl";
     field public static final String EXTRA_SHOW_PLMN = "android.telephony.extra.SHOW_PLMN";
     field public static final String EXTRA_SHOW_SPN = "android.telephony.extra.SHOW_SPN";
-    field public static final String EXTRA_SIM_COMBINATION_NAMES = "android.telephony.extra.SIM_COMBINATION_NAMES";
-    field public static final String EXTRA_SIM_COMBINATION_WARNING_TYPE = "android.telephony.extra.SIM_COMBINATION_WARNING_TYPE";
-    field public static final int EXTRA_SIM_COMBINATION_WARNING_TYPE_DUAL_CDMA = 1; // 0x1
-    field public static final int EXTRA_SIM_COMBINATION_WARNING_TYPE_NONE = 0; // 0x0
     field public static final String EXTRA_SIM_STATE = "android.telephony.extra.SIM_STATE";
     field public static final String EXTRA_SPN = "android.telephony.extra.SPN";
     field public static final String EXTRA_VISUAL_VOICEMAIL_ENABLED_BY_USER_BOOL = "android.telephony.extra.VISUAL_VOICEMAIL_ENABLED_BY_USER_BOOL";
@@ -924,7 +913,6 @@ package android.telephony {
     field public static final int INVALID_EMERGENCY_NUMBER_DB_VERSION = -1; // 0xffffffff
     field public static final int KEY_TYPE_EPDG = 1; // 0x1
     field public static final int KEY_TYPE_WLAN = 2; // 0x2
-    field public static final String MODEM_ACTIVITY_RESULT_KEY = "controller_activity";
     field public static final long NETWORK_TYPE_BITMASK_1xRTT = 64L; // 0x40L
     field public static final long NETWORK_TYPE_BITMASK_CDMA = 8L; // 0x8L
     field public static final long NETWORK_TYPE_BITMASK_EDGE = 2L; // 0x2L
diff --git a/telephony/java/android/telephony/TelephonyManager.java b/telephony/java/android/telephony/TelephonyManager.java
index 059692de134ed..b6c81cf2b9251 100644
--- a/telephony/java/android/telephony/TelephonyManager.java
+++ b/telephony/java/android/telephony/TelephonyManager.java
@@ -163,7 +163,6 @@ public class TelephonyManager {
      * into the ResultReceiver Bundle.
      * @hide
      */
-    @SystemApi
     public static final String MODEM_ACTIVITY_RESULT_KEY = "controller_activity";
 
     /**
@@ -1432,7 +1431,6 @@ public class TelephonyManager {
      *
      * @hide
      */
-    @SystemApi
     public static final String EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE =
             "android.telephony.extra.DEFAULT_SUBSCRIPTION_SELECT_TYPE";
 
@@ -1452,7 +1450,6 @@ public class TelephonyManager {
      * to indicate there's no need to re-select any default subscription.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_NONE = 0;
 
     /**
@@ -1460,7 +1457,6 @@ public class TelephonyManager {
      * to indicate there's a need to select default data subscription.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_DATA = 1;
 
     /**
@@ -1468,7 +1464,6 @@ public class TelephonyManager {
      * to indicate there's a need to select default voice call subscription.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_VOICE = 2;
 
     /**
@@ -1476,7 +1471,6 @@ public class TelephonyManager {
      * to indicate there's a need to select default sms subscription.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_SMS = 3;
 
     /**
@@ -1486,7 +1480,6 @@ public class TelephonyManager {
      * which subscription should be the default subscription.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_DEFAULT_SUBSCRIPTION_SELECT_TYPE_ALL = 4;
 
     /**
@@ -1496,7 +1489,6 @@ public class TelephonyManager {
      *
      * @hide
      */
-    @SystemApi
     public static final String EXTRA_SIM_COMBINATION_WARNING_TYPE =
             "android.telephony.extra.SIM_COMBINATION_WARNING_TYPE";
 
@@ -1513,7 +1505,6 @@ public class TelephonyManager {
      * to indicate there's no SIM combination warning.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_SIM_COMBINATION_WARNING_TYPE_NONE = 0;
 
     /**
@@ -1521,7 +1512,6 @@ public class TelephonyManager {
      * to indicate two active SIMs are both CDMA hence there might be functional limitation.
      * @hide
      */
-    @SystemApi
     public static final int EXTRA_SIM_COMBINATION_WARNING_TYPE_DUAL_CDMA = 1;
 
     /**
@@ -1532,7 +1522,6 @@ public class TelephonyManager {
      *
      * @hide
      */
-    @SystemApi
     public static final String EXTRA_SIM_COMBINATION_NAMES =
             "android.telephony.extra.SIM_COMBINATION_NAMES";
 
@@ -10140,7 +10129,6 @@ public class TelephonyManager {
      * {@link #MODEM_ACTIVITY_RESULT_KEY}.
      * @hide
      */
-    @SystemApi
     public void requestModemActivityInfo(@NonNull ResultReceiver result) {
         try {
             ITelephony service = getITelephony();