diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index 91f6fe57112e3..12f0afa88c69e 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -13239,8 +13239,10 @@ package android.telephony.ims {
     field public static final int DEREGISTERED_REASON_UNKNOWN = 0; // 0x0
     field public static final int DEREGISTERING_REASON_DESTROY_PENDING = 6; // 0x6
     field public static final int DEREGISTERING_REASON_FEATURE_TAGS_CHANGING = 5; // 0x5
+    field public static final int DEREGISTERING_REASON_LOSING_PDN = 7; // 0x7
     field public static final int DEREGISTERING_REASON_PDN_CHANGE = 3; // 0x3
     field public static final int DEREGISTERING_REASON_PROVISIONING_CHANGE = 4; // 0x4
+    field public static final int DEREGISTERING_REASON_UNSPECIFIED = 8; // 0x8
   }
 
   public static final class DelegateRegistrationState.Builder {
diff --git a/telephony/java/android/telephony/ims/DelegateRegistrationState.java b/telephony/java/android/telephony/ims/DelegateRegistrationState.java
index 1b1040430fd27..c2c9497cef3db 100644
--- a/telephony/java/android/telephony/ims/DelegateRegistrationState.java
+++ b/telephony/java/android/telephony/ims/DelegateRegistrationState.java
@@ -97,7 +97,24 @@ public final class DelegateRegistrationState implements Parcelable {
      */
     public static final int DEREGISTERING_REASON_DESTROY_PENDING = 6;
 
-    /** @hide */
+    /**
+     * This feature tag is deregistering because the PDN that the IMS registration is on
+     * is being torn down.
+     * <p>
+     * All open SIP Dialogs associated with this feature tag must be  closed
+     * using {@link SipDelegateConnection#cleanupSession(String)} before this operation can proceed.
+     */
+    public static final int DEREGISTERING_REASON_LOSING_PDN = 7;
+
+    /**
+     * This feature tag is deregistering because of an unspecified reason.
+     * <p>
+     * All open SIP Dialogs associated with this feature tag must be  closed
+     * using {@link SipDelegateConnection#cleanupSession(String)} before this operation can proceed.
+     */
+    public static final int DEREGISTERING_REASON_UNSPECIFIED = 8;
+
+/** @hide */
     @Retention(RetentionPolicy.SOURCE)
     @IntDef(prefix = "DEREGISTERED_REASON_", value = {
             DEREGISTERED_REASON_UNKNOWN,
@@ -113,7 +130,9 @@ public final class DelegateRegistrationState implements Parcelable {
             DEREGISTERING_REASON_PDN_CHANGE,
             DEREGISTERING_REASON_PROVISIONING_CHANGE,
             DEREGISTERING_REASON_FEATURE_TAGS_CHANGING,
-            DEREGISTERING_REASON_DESTROY_PENDING
+            DEREGISTERING_REASON_DESTROY_PENDING,
+            DEREGISTERING_REASON_LOSING_PDN,
+            DEREGISTERING_REASON_UNSPECIFIED
     })
     public @interface DeregisteringReason {}