diff --git a/Tethering/src/com/android/networkstack/tethering/Tethering.java b/Tethering/src/com/android/networkstack/tethering/Tethering.java
index a381621..e91ae85 100644
--- a/Tethering/src/com/android/networkstack/tethering/Tethering.java
+++ b/Tethering/src/com/android/networkstack/tethering/Tethering.java
@@ -1039,7 +1039,7 @@
             final boolean rndisEnabled = intent.getBooleanExtra(USB_FUNCTION_RNDIS, false);
             final boolean ncmEnabled = intent.getBooleanExtra(USB_FUNCTION_NCM, false);
 
-            mLog.log(String.format("USB bcast connected:%s configured:%s rndis:%s ncm:%s",
+            mLog.i(String.format("USB bcast connected:%s configured:%s rndis:%s ncm:%s",
                     usbConnected, usbConfigured, rndisEnabled, ncmEnabled));
 
             // There are three types of ACTION_USB_STATE:
@@ -1416,7 +1416,7 @@
 
         // If TETHERING_USB is forced to use ncm function, TETHERING_NCM would no longer be
         // available.
-        if (mConfig.isUsingNcm()) return TETHER_ERROR_SERVICE_UNAVAIL;
+        if (mConfig.isUsingNcm() && enable) return TETHER_ERROR_SERVICE_UNAVAIL;
 
         UsbManager usbManager = (UsbManager) mContext.getSystemService(Context.USB_SERVICE);
         usbManager.setCurrentFunctions(enable ? UsbManager.FUNCTION_NCM : UsbManager.FUNCTION_NONE);
@@ -2552,7 +2552,7 @@
             return;
         }
 
-        mLog.log("adding IpServer for: " + iface);
+        mLog.i("adding IpServer for: " + iface);
         final TetherState tetherState = new TetherState(
                 new IpServer(iface, mLooper, interfaceType, mLog, mNetd, mBpfCoordinator,
                              makeControlCallback(), mConfig.enableLegacyDhcpServer,
@@ -2567,7 +2567,7 @@
         if (tetherState == null) return;
 
         tetherState.ipServer.stop();
-        mLog.log("removing IpServer for: " + iface);
+        mLog.i("removing IpServer for: " + iface);
         mTetherStates.remove(iface);
     }
 
diff --git a/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java b/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java
index 31fcea4..d2f44d3 100644
--- a/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java
+++ b/Tethering/src/com/android/networkstack/tethering/TetheringConfiguration.java
@@ -176,7 +176,9 @@
         // us an interface name. Careful consideration needs to be given to
         // implications for Settings and for provisioning checks.
         tetherableWifiRegexs = getResourceStringArray(res, R.array.config_tether_wifi_regexs);
-        tetherableWigigRegexs = getResourceStringArray(res, R.array.config_tether_wigig_regexs);
+        // TODO: Remove entire wigig code once tethering module no longer support R devices.
+        tetherableWigigRegexs = SdkLevel.isAtLeastS()
+                ? new String[0] : getResourceStringArray(res, R.array.config_tether_wigig_regexs);
         tetherableWifiP2pRegexs = getResourceStringArray(
                 res, R.array.config_tether_wifi_p2p_regexs);
         tetherableBluetoothRegexs = getResourceStringArray(
diff --git a/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java b/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java
index af28dd7..9e0c880 100644
--- a/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java
+++ b/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java
@@ -2610,12 +2610,57 @@
         reset(mBluetoothAdapter, mBluetoothPan);
     }
 
+    private void runDualStackUsbTethering(final String expectedIface) throws Exception {
+        when(mNetd.interfaceGetList()).thenReturn(new String[] {expectedIface});
+        when(mRouterAdvertisementDaemon.start())
+                .thenReturn(true);
+        final UpstreamNetworkState upstreamState = buildMobileDualStackUpstreamState();
+        runUsbTethering(upstreamState);
+
+        verify(mNetd).interfaceGetList();
+        verify(mNetd).tetherAddForward(expectedIface, TEST_MOBILE_IFNAME);
+        verify(mNetd).ipfwdAddInterfaceForward(expectedIface, TEST_MOBILE_IFNAME);
+
+        verify(mRouterAdvertisementDaemon).start();
+        verify(mDhcpServer, timeout(DHCPSERVER_START_TIMEOUT_MS)).startWithCallbacks(
+                any(), any());
+        sendIPv6TetherUpdates(upstreamState);
+        assertSetIfaceToDadProxy(1 /* numOfCalls */, TEST_MOBILE_IFNAME /* ifaceName */);
+        verify(mRouterAdvertisementDaemon).buildNewRa(any(), notNull());
+        verify(mNetd).tetherApplyDnsInterfaces();
+    }
+
+    private void forceUsbTetheringUse(final int function) {
+        Settings.Global.putInt(mContentResolver, TETHER_FORCE_USB_FUNCTIONS, function);
+        final ContentObserver observer = mTethering.getSettingsObserverForTest();
+        observer.onChange(false /* selfChange */);
+        mLooper.dispatchAll();
+    }
+
+    private void verifyUsbTetheringStopDueToSettingChange(final String iface) {
+        verify(mUsbManager, times(2)).setCurrentFunctions(UsbManager.FUNCTION_NONE);
+        mTethering.interfaceRemoved(iface);
+        sendUsbBroadcast(true, true, -1 /* no functions enabled */);
+        reset(mUsbManager, mNetd, mDhcpServer, mRouterAdvertisementDaemon,
+                mIPv6TetheringCoordinator, mDadProxy);
+    }
+
     @Test
-    public void testUsbTetheringWithNcmFunction() throws Exception {
-        when(mResources.getInteger(R.integer.config_tether_usb_functions)).thenReturn(
-                TetheringConfiguration.TETHER_USB_NCM_FUNCTION);
+    public void testUsbFunctionConfigurationChange() throws Exception {
+        // Run TETHERING_NCM.
+        runNcmTethering();
+        verify(mDhcpServer, timeout(DHCPSERVER_START_TIMEOUT_MS).times(1)).startWithCallbacks(
+                any(), any());
+
+        // Change the USB tethering function to NCM. Because the USB tethering function was set to
+        // RNDIS (the default), tethering is stopped.
+        forceUsbTetheringUse(TETHER_USB_NCM_FUNCTION);
+        verifyUsbTetheringStopDueToSettingChange(TEST_NCM_IFNAME);
+
+        // TODO: move this into setup after allowing configure TEST_NCM_REGEX into
+        // config_tether_usb_regexs and config_tether_ncm_regexs at the same time.
         when(mResources.getStringArray(R.array.config_tether_usb_regexs))
-                .thenReturn(new String[] {TEST_NCM_REGEX});
+                .thenReturn(new String[] {TEST_RNDIS_REGEX, TEST_NCM_REGEX});
         sendConfigurationChanged();
 
         // If TETHERING_USB is forced to use ncm function, TETHERING_NCM would no longer be
@@ -2625,30 +2670,16 @@
         mLooper.dispatchAll();
         ncmResult.assertHasResult();
 
-        final UpstreamNetworkState upstreamState = buildMobileDualStackUpstreamState();
-        runUsbTethering(upstreamState);
+        // Run TETHERING_USB with ncm configuration.
+        runDualStackUsbTethering(TEST_NCM_IFNAME);
 
-        verify(mNetd).interfaceGetList();
-        verify(mNetd).tetherAddForward(TEST_NCM_IFNAME, TEST_MOBILE_IFNAME);
-        verify(mNetd).ipfwdAddInterfaceForward(TEST_NCM_IFNAME, TEST_MOBILE_IFNAME);
+        // Change configuration to rndis.
+        forceUsbTetheringUse(TETHER_USB_RNDIS_FUNCTION);
+        verifyUsbTetheringStopDueToSettingChange(TEST_NCM_IFNAME);
 
-        verify(mRouterAdvertisementDaemon).start();
-        verify(mDhcpServer, timeout(DHCPSERVER_START_TIMEOUT_MS)).startWithCallbacks(
-                any(), any());
-        sendIPv6TetherUpdates(upstreamState);
-        assertSetIfaceToDadProxy(1 /* numOfCalls */, TEST_MOBILE_IFNAME /* ifaceName */);
-        verify(mRouterAdvertisementDaemon).buildNewRa(any(), notNull());
-        verify(mNetd).tetherApplyDnsInterfaces();
-
-        Settings.Global.putInt(mContentResolver, TETHER_FORCE_USB_FUNCTIONS,
-                TETHER_USB_RNDIS_FUNCTION);
-        final ContentObserver observer = mTethering.getSettingsObserverForTest();
-        observer.onChange(false /* selfChange */);
-        mLooper.dispatchAll();
-        // stop TETHERING_USB and TETHERING_NCM
-        verify(mUsbManager, times(2)).setCurrentFunctions(UsbManager.FUNCTION_NONE);
-        mTethering.interfaceRemoved(TEST_NCM_IFNAME);
-        sendUsbBroadcast(true, true, -1 /* function */);
+        // Run TETHERING_USB with rndis configuration.
+        runDualStackUsbTethering(TEST_RNDIS_IFNAME);
+        runStopUSBTethering();
     }
     // TODO: Test that a request for hotspot mode doesn't interfere with an
     // already operating tethering mode interface.
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index 94f652d..7b58503 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -6288,7 +6288,8 @@
                 callingAttributionTag);
         if (VDBG) log("pendingListenForNetwork for " + nri);
 
-        mHandler.sendMessage(mHandler.obtainMessage(EVENT_REGISTER_NETWORK_LISTENER, nri));
+        mHandler.sendMessage(mHandler.obtainMessage(
+                    EVENT_REGISTER_NETWORK_LISTENER_WITH_INTENT, nri));
     }
 
     /** Returns the next Network provider ID. */
diff --git a/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java b/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
index 9ad9522..4403a0e 100644
--- a/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
+++ b/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
@@ -76,6 +76,7 @@
 import static com.android.compatibility.common.util.SystemUtil.callWithShellPermissionIdentity;
 import static com.android.compatibility.common.util.SystemUtil.runShellCommand;
 import static com.android.compatibility.common.util.SystemUtil.runWithShellPermissionIdentity;
+import static com.android.modules.utils.build.SdkLevel.isAtLeastS;
 import static com.android.networkstack.apishim.ConstantsShim.BLOCKED_REASON_LOCKDOWN_VPN;
 import static com.android.networkstack.apishim.ConstantsShim.BLOCKED_REASON_NONE;
 import static com.android.testutils.MiscAsserts.assertThrows;
@@ -943,8 +944,8 @@
             // noticeably flaky.
             Thread.sleep(NO_CALLBACK_TIMEOUT_MS);
 
-            // TODO: BUG (b/189868426): this should also apply to listens
-            if (!useListen) {
+            // For R- frameworks, listens will receive duplicated callbacks. See b/189868426.
+            if (isAtLeastS() || !useListen) {
                 assertEquals("PendingIntent should only be received once", 1, receivedCount.get());
             }
         } finally {
@@ -959,8 +960,8 @@
             boolean useListen) {
         assertArrayEquals(filed.networkCapabilities.getCapabilities(),
                 broadcasted.networkCapabilities.getCapabilities());
-        // TODO: BUG (b/189868426): this should also apply to listens
-        if (useListen) return;
+        // For R- frameworks, listens will receive duplicated callbacks. See b/189868426.
+        if (!isAtLeastS() && useListen) return;
         assertArrayEquals(filed.networkCapabilities.getTransportTypes(),
                 broadcasted.networkCapabilities.getTransportTypes());
     }
diff --git a/tests/unit/java/com/android/server/ConnectivityServiceTest.java b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
index 2b191e1..2aa95ee 100644
--- a/tests/unit/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/unit/java/com/android/server/ConnectivityServiceTest.java
@@ -5865,37 +5865,59 @@
     @Test
     public void testNetworkCallbackMaximum() throws Exception {
         final int MAX_REQUESTS = 100;
-        final int CALLBACKS = 89;
-        final int INTENTS = 11;
+        final int CALLBACKS = 87;
+        final int DIFF_INTENTS = 10;
+        final int SAME_INTENTS = 10;
         final int SYSTEM_ONLY_MAX_REQUESTS = 250;
-        assertEquals(MAX_REQUESTS, CALLBACKS + INTENTS);
+        // Assert 1 (Default request filed before testing) + CALLBACKS + DIFF_INTENTS +
+        // 1 (same intent) = MAX_REQUESTS - 1, since the capacity is MAX_REQUEST - 1.
+        assertEquals(MAX_REQUESTS - 1, 1 + CALLBACKS + DIFF_INTENTS + 1);
 
         NetworkRequest networkRequest = new NetworkRequest.Builder().build();
         ArrayList<Object> registered = new ArrayList<>();
 
-        int j = 0;
-        while (j++ < CALLBACKS / 2) {
-            NetworkCallback cb = new NetworkCallback();
-            mCm.requestNetwork(networkRequest, cb);
+        for (int j = 0; j < CALLBACKS; j++) {
+            final NetworkCallback cb = new NetworkCallback();
+            if (j < CALLBACKS / 2) {
+                mCm.requestNetwork(networkRequest, cb);
+            } else {
+                mCm.registerNetworkCallback(networkRequest, cb);
+            }
             registered.add(cb);
         }
-        while (j++ < CALLBACKS) {
-            NetworkCallback cb = new NetworkCallback();
-            mCm.registerNetworkCallback(networkRequest, cb);
-            registered.add(cb);
+
+        // Since ConnectivityService will de-duplicate the request with the same intent,
+        // register multiple times does not really increase multiple requests.
+        final PendingIntent same_pi = PendingIntent.getBroadcast(mContext, 0 /* requestCode */,
+                new Intent("same"), FLAG_IMMUTABLE);
+        for (int j = 0; j < SAME_INTENTS; j++) {
+            mCm.registerNetworkCallback(networkRequest, same_pi);
+            // Wait for the requests with the same intent to be de-duplicated. Because
+            // ConnectivityService side incrementCountOrThrow in binder, decrementCount in handler
+            // thread, waitForIdle is needed to ensure decrementCount being invoked for same intent
+            // requests before doing further tests.
+            waitForIdle();
         }
-        j = 0;
-        while (j++ < INTENTS / 2) {
-            final PendingIntent pi = PendingIntent.getBroadcast(mContext, 0 /* requestCode */,
-                    new Intent("a" + j), FLAG_IMMUTABLE);
-            mCm.requestNetwork(networkRequest, pi);
-            registered.add(pi);
+        for (int j = 0; j < SAME_INTENTS; j++) {
+            mCm.requestNetwork(networkRequest, same_pi);
+            // Wait for the requests with the same intent to be de-duplicated.
+            // Refer to the reason above.
+            waitForIdle();
         }
-        while (j++ < INTENTS) {
-            final PendingIntent pi = PendingIntent.getBroadcast(mContext, 0 /* requestCode */,
-                    new Intent("b" + j), FLAG_IMMUTABLE);
-            mCm.registerNetworkCallback(networkRequest, pi);
-            registered.add(pi);
+        registered.add(same_pi);
+
+        for (int j = 0; j < DIFF_INTENTS; j++) {
+            if (j < DIFF_INTENTS / 2) {
+                final PendingIntent pi = PendingIntent.getBroadcast(mContext, 0 /* requestCode */,
+                        new Intent("a" + j), FLAG_IMMUTABLE);
+                mCm.requestNetwork(networkRequest, pi);
+                registered.add(pi);
+            } else {
+                final PendingIntent pi = PendingIntent.getBroadcast(mContext, 0 /* requestCode */,
+                        new Intent("b" + j), FLAG_IMMUTABLE);
+                mCm.registerNetworkCallback(networkRequest, pi);
+                registered.add(pi);
+            }
         }
 
         // Test that the limit is enforced when MAX_REQUESTS simultaneous requests are added.
@@ -5945,10 +5967,10 @@
 
         for (Object o : registered) {
             if (o instanceof NetworkCallback) {
-                mCm.unregisterNetworkCallback((NetworkCallback)o);
+                mCm.unregisterNetworkCallback((NetworkCallback) o);
             }
             if (o instanceof PendingIntent) {
-                mCm.unregisterNetworkCallback((PendingIntent)o);
+                mCm.unregisterNetworkCallback((PendingIntent) o);
             }
         }
         waitForIdle();