diff --git a/service-t/src/com/android/server/net/NetworkStatsObservers.java b/service-t/src/com/android/server/net/NetworkStatsObservers.java
index df4e7f5..1cd670a 100644
--- a/service-t/src/com/android/server/net/NetworkStatsObservers.java
+++ b/service-t/src/com/android/server/net/NetworkStatsObservers.java
@@ -198,7 +198,7 @@
 
         if (LOG) Log.d(TAG, "Unregistering " + requestInfo);
         mDataUsageRequests.remove(request.requestId);
-        mDataUsageRequestsPerUid.decrementCountOrThrow(callingUid);
+        mDataUsageRequestsPerUid.decrementCountOrThrow(requestInfo.mCallingUid);
         requestInfo.unlinkDeathRecipient();
         requestInfo.callCallback(NetworkStatsManager.CALLBACK_RELEASED);
     }
diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
index 63e6501..dc09bc2 100644
--- a/service-t/src/com/android/server/net/NetworkStatsService.java
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -253,7 +253,8 @@
             "netstats_import_legacy_target_attempts";
     static final int DEFAULT_NETSTATS_IMPORT_LEGACY_TARGET_ATTEMPTS = 1;
     static final String NETSTATS_IMPORT_ATTEMPTS_COUNTER_NAME = "import.attempts";
-    static final String NETSTATS_IMPORT_SUCCESS_COUNTER_NAME = "import.successes";
+    static final String NETSTATS_IMPORT_SUCCESSES_COUNTER_NAME = "import.successes";
+    static final String NETSTATS_IMPORT_FALLBACKS_COUNTER_NAME = "import.fallbacks";
 
     private final Context mContext;
     private final NetworkStatsFactory mStatsFactory;
@@ -273,10 +274,11 @@
     private final AlertObserver mAlertObserver = new AlertObserver();
 
     // Persistent counters that backed by AtomicFile which stored in the data directory as a file,
-    // to track attempts/successes count across reboot. Note that these counter values will be
-    // rollback as the module rollbacks.
+    // to track attempts/successes/fallbacks count across reboot. Note that these counter values
+    // will be rollback as the module rollbacks.
     private PersistentInt mImportLegacyAttemptsCounter = null;
     private PersistentInt mImportLegacySuccessesCounter = null;
+    private PersistentInt mImportLegacyFallbacksCounter = null;
 
     @VisibleForTesting
     public static final String ACTION_NETWORK_STATS_POLL =
@@ -619,21 +621,14 @@
         }
 
         /**
-         * Create the persistent counter that counts total import legacy stats attempts.
+         * Create a persistent counter for given directory and name.
          */
-        public PersistentInt createImportLegacyAttemptsCounter(@NonNull Path path)
+        public PersistentInt createPersistentCounter(@NonNull Path dir, @NonNull String name)
                 throws IOException {
             // TODO: Modify PersistentInt to call setStartTime every time a write is made.
             //  Create and pass a real logger here.
-            return new PersistentInt(path.toString(), null /* logger */);
-        }
-
-        /**
-         * Create the persistent counter that counts total import legacy stats successes.
-         */
-        public PersistentInt createImportLegacySuccessesCounter(@NonNull Path path)
-                throws IOException {
-            return new PersistentInt(path.toString(), null /* logger */);
+            final String path = dir.resolve(name).toString();
+            return new PersistentInt(path, null /* logger */);
         }
 
         /**
@@ -911,10 +906,12 @@
             return;
         }
         try {
-            mImportLegacyAttemptsCounter = mDeps.createImportLegacyAttemptsCounter(
-                    mStatsDir.toPath().resolve(NETSTATS_IMPORT_ATTEMPTS_COUNTER_NAME));
-            mImportLegacySuccessesCounter = mDeps.createImportLegacySuccessesCounter(
-                    mStatsDir.toPath().resolve(NETSTATS_IMPORT_SUCCESS_COUNTER_NAME));
+            mImportLegacyAttemptsCounter = mDeps.createPersistentCounter(mStatsDir.toPath(),
+                    NETSTATS_IMPORT_ATTEMPTS_COUNTER_NAME);
+            mImportLegacySuccessesCounter = mDeps.createPersistentCounter(mStatsDir.toPath(),
+                    NETSTATS_IMPORT_SUCCESSES_COUNTER_NAME);
+            mImportLegacyFallbacksCounter = mDeps.createPersistentCounter(mStatsDir.toPath(),
+                    NETSTATS_IMPORT_FALLBACKS_COUNTER_NAME);
         } catch (IOException e) {
             Log.wtf(TAG, "Failed to create persistent counters, skip.", e);
             return;
@@ -922,15 +919,24 @@
 
         final int targetAttempts = mDeps.getImportLegacyTargetAttempts();
         final int attempts;
+        final int fallbacks;
         try {
             attempts = mImportLegacyAttemptsCounter.get();
+            fallbacks = mImportLegacyFallbacksCounter.get();
         } catch (IOException e) {
-            Log.wtf(TAG, "Failed to read attempts counter, skip.", e);
+            Log.wtf(TAG, "Failed to read counters, skip.", e);
             return;
         }
-        if (attempts >= targetAttempts) return;
+        // If fallbacks is not zero, proceed with reading only to give signals from dogfooders.
+        // TODO(b/233752318): Remove fallbacks counter check before T formal release.
+        if (attempts >= targetAttempts && fallbacks == 0) return;
 
-        Log.i(TAG, "Starting import : attempts " + attempts + "/" + targetAttempts);
+        final boolean dryRunImportOnly = (attempts >= targetAttempts);
+        if (dryRunImportOnly) {
+            Log.i(TAG, "Starting import : only perform read");
+        } else {
+            Log.i(TAG, "Starting import : attempts " + attempts + "/" + targetAttempts);
+        }
 
         final MigrationInfo[] migrations = new MigrationInfo[]{
                 new MigrationInfo(mDevRecorder), new MigrationInfo(mXtRecorder),
@@ -987,6 +993,10 @@
                 }
             }
 
+            // For cases where the fallbacks is not zero but target attempts counts reached,
+            // only perform reads above and return here.
+            if (dryRunImportOnly) return;
+
             // Find the latest end time.
             for (final MigrationInfo migration : migrations) {
                 final long migrationEnd = migration.collection.getEndMillis();
@@ -1009,11 +1019,7 @@
                 migration.recorder.importCollectionLocked(migration.collection);
             }
 
-            if (endedWithFallback) {
-                Log.wtf(TAG, "Imported platform collections with legacy fallback");
-            } else {
-                Log.i(TAG, "Successfully imported platform collections");
-            }
+            // Success normally or uses fallback method.
         } catch (Throwable e) {
             // The code above calls OEM code that may behave differently across devices.
             // It can throw any exception including RuntimeExceptions and
@@ -1053,10 +1059,17 @@
         // Success ! No need to import again next time.
         try {
             mImportLegacyAttemptsCounter.set(targetAttempts);
-            // The successes counter is only for debugging. Hence, the synchronization
-            // between these two counters are not very critical.
-            final int successCount = mImportLegacySuccessesCounter.get();
-            mImportLegacySuccessesCounter.set(successCount + 1);
+            if (endedWithFallback) {
+                Log.wtf(TAG, "Imported platform collections with legacy fallback");
+                final int fallbacksCount = mImportLegacyFallbacksCounter.get();
+                mImportLegacyFallbacksCounter.set(fallbacksCount + 1);
+            } else {
+                Log.i(TAG, "Successfully imported platform collections");
+                // The successes counter is only for debugging. Hence, the synchronization
+                // between successes counter and attempts counter are not very critical.
+                final int successCount = mImportLegacySuccessesCounter.get();
+                mImportLegacySuccessesCounter.set(successCount + 1);
+            }
         } catch (IOException e) {
             Log.wtf(TAG, "Succeed but failed to update counters.", e);
         }
@@ -2478,6 +2491,9 @@
                     pw.print("platform legacy stats import successes count",
                             mImportLegacySuccessesCounter.get());
                     pw.println();
+                    pw.print("platform legacy stats import fallbacks count",
+                            mImportLegacyFallbacksCounter.get());
+                    pw.println();
                 } catch (IOException e) {
                     pw.println("(failed to dump platform legacy stats import counters)");
                 }
diff --git a/tests/unit/java/com/android/server/ConnectivityServiceTest.java b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
index 7ee4031..44550e6 100644
--- a/tests/unit/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
@@ -348,6 +348,7 @@
 import com.android.net.module.util.CollectionUtils;
 import com.android.net.module.util.LocationPermissionChecker;
 import com.android.networkstack.apishim.NetworkAgentConfigShimImpl;
+import com.android.networkstack.apishim.api29.ConstantsShim;
 import com.android.server.ConnectivityService.ConnectivityDiagnosticsCallbackInfo;
 import com.android.server.ConnectivityService.NetworkRequestInfo;
 import com.android.server.ConnectivityServiceTest.ConnectivityServiceDependencies.ReportedInterfaces;
@@ -659,7 +660,8 @@
         @Override
         public ComponentName startService(Intent service) {
             final String action = service.getAction();
-            if (!VpnConfig.SERVICE_INTERFACE.equals(action)) {
+            if (!VpnConfig.SERVICE_INTERFACE.equals(action)
+                    && !ConstantsShim.ACTION_VPN_MANAGER_EVENT.equals(action)) {
                 fail("Attempt to start unknown service, action=" + action);
             }
             return new ComponentName(service.getPackage(), "com.android.test.Service");
diff --git a/tests/unit/java/com/android/server/connectivity/VpnTest.java b/tests/unit/java/com/android/server/connectivity/VpnTest.java
index 59d7378..bae0433 100644
--- a/tests/unit/java/com/android/server/connectivity/VpnTest.java
+++ b/tests/unit/java/com/android/server/connectivity/VpnTest.java
@@ -27,6 +27,7 @@
 import static android.net.ConnectivityManager.NetworkCallback;
 import static android.net.INetd.IF_STATE_DOWN;
 import static android.net.INetd.IF_STATE_UP;
+import static android.net.VpnManager.TYPE_VPN_PLATFORM;
 import static android.os.Build.VERSION_CODES.S_V2;
 import static android.os.UserHandle.PER_USER_RANGE;
 
@@ -56,6 +57,7 @@
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.timeout;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -67,6 +69,7 @@
 import android.app.NotificationManager;
 import android.app.PendingIntent;
 import android.content.Context;
+import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
@@ -93,6 +96,7 @@
 import android.net.RouteInfo;
 import android.net.UidRangeParcel;
 import android.net.VpnManager;
+import android.net.VpnProfileState;
 import android.net.VpnService;
 import android.net.VpnTransportInfo;
 import android.net.ipsec.ike.IkeSessionCallback;
@@ -126,6 +130,7 @@
 import com.android.testutils.DevSdkIgnoreRule;
 import com.android.testutils.DevSdkIgnoreRunner;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
@@ -285,6 +290,11 @@
         doReturn(PERMISSION_DENIED).when(mContext).checkCallingOrSelfPermission(any());
     }
 
+    @After
+    public void tearDown() throws Exception {
+        doReturn(PERMISSION_DENIED).when(mContext).checkCallingOrSelfPermission(CONTROL_VPN);
+    }
+
     private <T> void mockService(Class<T> clazz, String name, T service) {
         doReturn(service).when(mContext).getSystemService(name);
         doReturn(name).when(mContext).getSystemServiceName(clazz);
@@ -902,6 +912,30 @@
         verify(mVpnProfileStore).get(eq(vpn.getProfileNameForPackage(TEST_VPN_PKG)));
     }
 
+    private void verifyPlatformVpnIsActivated(String packageName) {
+        verify(mAppOps).noteOpNoThrow(
+                eq(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN),
+                eq(Process.myUid()),
+                eq(packageName),
+                eq(null) /* attributionTag */,
+                eq(null) /* message */);
+        verify(mAppOps).startOp(
+                eq(AppOpsManager.OPSTR_ESTABLISH_VPN_MANAGER),
+                eq(Process.myUid()),
+                eq(packageName),
+                eq(null) /* attributionTag */,
+                eq(null) /* message */);
+    }
+
+    private void verifyPlatformVpnIsDeactivated(String packageName) {
+        // Add a small delay to double confirm that finishOp is only called once.
+        verify(mAppOps, after(100)).finishOp(
+                eq(AppOpsManager.OPSTR_ESTABLISH_VPN_MANAGER),
+                eq(Process.myUid()),
+                eq(packageName),
+                eq(null) /* attributionTag */);
+    }
+
     @Test
     public void testStartVpnProfile() throws Exception {
         final Vpn vpn = createVpnAndSetupUidChecks(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN);
@@ -912,13 +946,7 @@
         vpn.startVpnProfile(TEST_VPN_PKG);
 
         verify(mVpnProfileStore).get(eq(vpn.getProfileNameForPackage(TEST_VPN_PKG)));
-        verify(mAppOps)
-                .noteOpNoThrow(
-                        eq(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN),
-                        eq(Process.myUid()),
-                        eq(TEST_VPN_PKG),
-                        eq(null) /* attributionTag */,
-                        eq(null) /* message */);
+        verifyPlatformVpnIsActivated(TEST_VPN_PKG);
     }
 
     @Test
@@ -930,7 +958,7 @@
 
         vpn.startVpnProfile(TEST_VPN_PKG);
 
-        // Verify that the the ACTIVATE_VPN appop was checked, but no error was thrown.
+        // Verify that the ACTIVATE_VPN appop was checked, but no error was thrown.
         verify(mAppOps).noteOpNoThrow(AppOpsManager.OPSTR_ACTIVATE_VPN, Process.myUid(),
                 TEST_VPN_PKG, null /* attributionTag */, null /* message */);
     }
@@ -1015,18 +1043,7 @@
         when(mVpnProfileStore.get(vpn.getProfileNameForPackage(TEST_VPN_PKG)))
                 .thenReturn(mVpnProfile.encode());
         vpn.startVpnProfile(TEST_VPN_PKG);
-        verify(mAppOps).noteOpNoThrow(
-                eq(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN),
-                eq(Process.myUid()),
-                eq(TEST_VPN_PKG),
-                eq(null) /* attributionTag */,
-                eq(null) /* message */);
-        verify(mAppOps).startOp(
-                eq(AppOpsManager.OPSTR_ESTABLISH_VPN_MANAGER),
-                eq(Process.myUid()),
-                eq(TEST_VPN_PKG),
-                eq(null) /* attributionTag */,
-                eq(null) /* message */);
+        verifyPlatformVpnIsActivated(TEST_VPN_PKG);
         // Add a small delay to make sure that startOp is only called once.
         verify(mAppOps, after(100).times(1)).startOp(
                 eq(AppOpsManager.OPSTR_ESTABLISH_VPN_MANAGER),
@@ -1042,12 +1059,7 @@
                 eq(null) /* attributionTag */,
                 eq(null) /* message */);
         vpn.stopVpnProfile(TEST_VPN_PKG);
-        // Add a small delay to double confirm that startOp is only called once.
-        verify(mAppOps, after(100)).finishOp(
-                eq(AppOpsManager.OPSTR_ESTABLISH_VPN_MANAGER),
-                eq(Process.myUid()),
-                eq(TEST_VPN_PKG),
-                eq(null) /* attributionTag */);
+        verifyPlatformVpnIsDeactivated(TEST_VPN_PKG);
     }
 
     @Test
@@ -1083,6 +1095,128 @@
                 eq(null) /* message */);
     }
 
+    private void verifyVpnManagerEvent(String sessionKey, String category, int errorClass,
+            int errorCode, VpnProfileState... profileState) {
+        final Context userContext =
+                mContext.createContextAsUser(UserHandle.of(primaryUser.id), 0 /* flags */);
+        final ArgumentCaptor<Intent> intentArgumentCaptor = ArgumentCaptor.forClass(Intent.class);
+
+        final int verifyTimes = (profileState == null) ? 1 : profileState.length;
+        verify(userContext, times(verifyTimes)).startService(intentArgumentCaptor.capture());
+
+        for (int i = 0; i < verifyTimes; i++) {
+            final Intent intent = intentArgumentCaptor.getAllValues().get(i);
+            assertEquals(sessionKey, intent.getStringExtra(VpnManager.EXTRA_SESSION_KEY));
+            final Set<String> categories = intent.getCategories();
+            assertTrue(categories.contains(category));
+            assertEquals(errorClass,
+                    intent.getIntExtra(VpnManager.EXTRA_ERROR_CLASS, -1 /* defaultValue */));
+            assertEquals(errorCode,
+                    intent.getIntExtra(VpnManager.EXTRA_ERROR_CODE, -1 /* defaultValue */));
+            if (profileState != null) {
+                assertEquals(profileState[i], intent.getParcelableExtra(
+                        VpnManager.EXTRA_VPN_PROFILE_STATE, VpnProfileState.class));
+            }
+        }
+        reset(userContext);
+    }
+
+    @Test
+    public void testVpnManagerEventForUserDeactivated() throws Exception {
+        assumeTrue(SdkLevel.isAtLeastT());
+        // For security reasons, Vpn#prepare() will check that oldPackage and newPackage are either
+        // null or the package of the caller. This test will call Vpn#prepare() to pretend the old
+        // VPN is replaced by a new one. But only Settings can change to some other packages, and
+        // this is checked with CONTROL_VPN so simulate holding CONTROL_VPN in order to pass the
+        // security checks.
+        doReturn(PERMISSION_GRANTED).when(mContext).checkCallingOrSelfPermission(CONTROL_VPN);
+        final Vpn vpn = createVpnAndSetupUidChecks(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN);
+        when(mVpnProfileStore.get(vpn.getProfileNameForPackage(TEST_VPN_PKG)))
+                .thenReturn(mVpnProfile.encode());
+
+        // Test the case that the user deactivates the vpn in vpn app.
+        final String sessionKey1 = vpn.startVpnProfile(TEST_VPN_PKG);
+        verifyPlatformVpnIsActivated(TEST_VPN_PKG);
+        vpn.stopVpnProfile(TEST_VPN_PKG);
+        verifyPlatformVpnIsDeactivated(TEST_VPN_PKG);
+        // CATEGORY_EVENT_DEACTIVATED_BY_USER is not an error event, so both of errorClass and
+        // errorCode won't be set.
+        verifyVpnManagerEvent(sessionKey1, VpnManager.CATEGORY_EVENT_DEACTIVATED_BY_USER,
+                -1 /* errorClass */, -1 /* errorCode */, null /* profileState */);
+        reset(mAppOps);
+
+        // Test the case that the user chooses another vpn and the original one is replaced.
+        final String sessionKey2 = vpn.startVpnProfile(TEST_VPN_PKG);
+        verifyPlatformVpnIsActivated(TEST_VPN_PKG);
+        vpn.prepare(TEST_VPN_PKG, "com.new.vpn" /* newPackage */, TYPE_VPN_PLATFORM);
+        verifyPlatformVpnIsDeactivated(TEST_VPN_PKG);
+        // CATEGORY_EVENT_DEACTIVATED_BY_USER is not an error event, so both of errorClass and
+        // errorCode won't be set.
+        verifyVpnManagerEvent(sessionKey2, VpnManager.CATEGORY_EVENT_DEACTIVATED_BY_USER,
+                -1 /* errorClass */, -1 /* errorCode */, null /* profileState */);
+    }
+
+    @Test
+    public void testVpnManagerEventForAlwaysOnChanged() throws Exception {
+        assumeTrue(SdkLevel.isAtLeastT());
+        // Calling setAlwaysOnPackage() needs to hold CONTROL_VPN.
+        doReturn(PERMISSION_GRANTED).when(mContext).checkCallingOrSelfPermission(CONTROL_VPN);
+        final Vpn vpn = createVpn(primaryUser.id);
+        // Enable VPN always-on for PKGS[1].
+        assertTrue(vpn.setAlwaysOnPackage(PKGS[1], false /* lockdown */,
+                null /* lockdownAllowlist */));
+        verifyVpnManagerEvent(null /* sessionKey */,
+                VpnManager.CATEGORY_EVENT_ALWAYS_ON_STATE_CHANGED, -1 /* errorClass */,
+                -1 /* errorCode */, new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, true /* alwaysOn */, false /* lockdown */));
+
+        // Enable VPN lockdown for PKGS[1].
+        assertTrue(vpn.setAlwaysOnPackage(PKGS[1], true /* lockdown */,
+                null /* lockdownAllowlist */));
+        verifyVpnManagerEvent(null /* sessionKey */,
+                VpnManager.CATEGORY_EVENT_ALWAYS_ON_STATE_CHANGED, -1 /* errorClass */,
+                -1 /* errorCode */, new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, true /* alwaysOn */, true /* lockdown */));
+
+        // Disable VPN lockdown for PKGS[1].
+        assertTrue(vpn.setAlwaysOnPackage(PKGS[1], false /* lockdown */,
+                null /* lockdownAllowlist */));
+        verifyVpnManagerEvent(null /* sessionKey */,
+                VpnManager.CATEGORY_EVENT_ALWAYS_ON_STATE_CHANGED, -1 /* errorClass */,
+                -1 /* errorCode */, new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, true /* alwaysOn */, false /* lockdown */));
+
+        // Disable VPN always-on.
+        assertTrue(vpn.setAlwaysOnPackage(null, false /* lockdown */,
+                null /* lockdownAllowlist */));
+        verifyVpnManagerEvent(null /* sessionKey */,
+                VpnManager.CATEGORY_EVENT_ALWAYS_ON_STATE_CHANGED, -1 /* errorClass */,
+                -1 /* errorCode */, new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, false /* alwaysOn */, false /* lockdown */));
+
+        // Enable VPN always-on for PKGS[1] again.
+        assertTrue(vpn.setAlwaysOnPackage(PKGS[1], false /* lockdown */,
+                null /* lockdownAllowlist */));
+        verifyVpnManagerEvent(null /* sessionKey */,
+                VpnManager.CATEGORY_EVENT_ALWAYS_ON_STATE_CHANGED, -1 /* errorClass */,
+                -1 /* errorCode */, new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, true /* alwaysOn */, false /* lockdown */));
+
+        // Enable VPN always-on for PKGS[2].
+        assertTrue(vpn.setAlwaysOnPackage(PKGS[2], false /* lockdown */,
+                null /* lockdownAllowlist */));
+        // PKGS[1] is replaced with PKGS[2].
+        // Pass 2 VpnProfileState objects to verifyVpnManagerEvent(), the first one is sent to
+        // PKGS[1] to notify PKGS[1] that the VPN always-on is disabled, the second one is sent to
+        // PKGS[2] to notify PKGS[2] that the VPN always-on is enabled.
+        verifyVpnManagerEvent(null /* sessionKey */,
+                VpnManager.CATEGORY_EVENT_ALWAYS_ON_STATE_CHANGED, -1 /* errorClass */,
+                -1 /* errorCode */, new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, false /* alwaysOn */, false /* lockdown */),
+                new VpnProfileState(VpnProfileState.STATE_DISCONNECTED,
+                        null /* sessionKey */, true /* alwaysOn */, false /* lockdown */));
+    }
+
     @Test
     public void testSetPackageAuthorizationVpnService() throws Exception {
         final Vpn vpn = createVpnAndSetupUidChecks();
@@ -1100,7 +1234,7 @@
     public void testSetPackageAuthorizationPlatformVpn() throws Exception {
         final Vpn vpn = createVpnAndSetupUidChecks();
 
-        assertTrue(vpn.setPackageAuthorization(TEST_VPN_PKG, VpnManager.TYPE_VPN_PLATFORM));
+        assertTrue(vpn.setPackageAuthorization(TEST_VPN_PKG, TYPE_VPN_PLATFORM));
         verify(mAppOps)
                 .setMode(
                         eq(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN),
diff --git a/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java b/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java
index e8c9637..5747e10 100644
--- a/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java
+++ b/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java
@@ -274,8 +274,12 @@
 
         mStatsObservers.unregister(request, UID_BLUE);
         waitForObserverToIdle();
-
         Mockito.verifyZeroInteractions(mUsageCallbackBinder);
+
+        // Verify that system uid can unregister for other uids.
+        mStatsObservers.unregister(request, Process.SYSTEM_UID);
+        waitForObserverToIdle();
+        mUsageCallback.expectOnCallbackReleased(request);
     }
 
     private NetworkIdentitySet makeTestIdentSet() {
diff --git a/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java b/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
index f1820b3..d37ae23 100644
--- a/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
+++ b/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
@@ -67,6 +67,9 @@
 
 import static com.android.net.module.util.NetworkStatsUtils.SUBSCRIBER_ID_MATCH_RULE_EXACT;
 import static com.android.server.net.NetworkStatsService.ACTION_NETWORK_STATS_POLL;
+import static com.android.server.net.NetworkStatsService.NETSTATS_IMPORT_ATTEMPTS_COUNTER_NAME;
+import static com.android.server.net.NetworkStatsService.NETSTATS_IMPORT_FALLBACKS_COUNTER_NAME;
+import static com.android.server.net.NetworkStatsService.NETSTATS_IMPORT_SUCCESSES_COUNTER_NAME;
 import static com.android.testutils.DevSdkIgnoreRuleKt.SC_V2;
 
 import static org.junit.Assert.assertEquals;
@@ -141,6 +144,7 @@
 import com.android.testutils.TestableNetworkStatsProviderBinder;
 
 import java.io.File;
+import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.time.Clock;
@@ -239,6 +243,7 @@
     private int mImportLegacyTargetAttempts = 0;
     private @Mock PersistentInt mImportLegacyAttemptsCounter;
     private @Mock PersistentInt mImportLegacySuccessesCounter;
+    private @Mock PersistentInt mImportLegacyFallbacksCounter;
 
     private class MockContext extends BroadcastInterceptingContext {
         private final Context mBaseContext;
@@ -379,15 +384,18 @@
             }
 
             @Override
-            public PersistentInt createImportLegacyAttemptsCounter(
-                    @androidx.annotation.NonNull Path path) {
-                return mImportLegacyAttemptsCounter;
-            }
-
-            @Override
-            public PersistentInt createImportLegacySuccessesCounter(
-                    @androidx.annotation.NonNull Path path) {
-                return mImportLegacySuccessesCounter;
+            public PersistentInt createPersistentCounter(@androidx.annotation.NonNull Path dir,
+                    @androidx.annotation.NonNull String name) throws IOException {
+                switch (name) {
+                    case NETSTATS_IMPORT_ATTEMPTS_COUNTER_NAME:
+                        return mImportLegacyAttemptsCounter;
+                    case NETSTATS_IMPORT_SUCCESSES_COUNTER_NAME:
+                        return mImportLegacySuccessesCounter;
+                    case NETSTATS_IMPORT_FALLBACKS_COUNTER_NAME:
+                        return mImportLegacyFallbacksCounter;
+                    default:
+                        throw new IllegalArgumentException("Unknown counter name: " + name);
+                }
             }
 
             @Override
@@ -1861,7 +1869,7 @@
     }
 
     private NetworkStatsCollection getLegacyCollection(String prefix, boolean includeTags) {
-        final NetworkStatsRecorder recorder = makeTestRecorder(mLegacyStatsDir, PREFIX_DEV,
+        final NetworkStatsRecorder recorder = makeTestRecorder(mLegacyStatsDir, prefix,
                 mSettings.getDevConfig(), includeTags);
         return recorder.getOrLoadCompleteLocked();
     }