diff --git a/src/com/android/phone/CarrierConfigLoader.java b/src/com/android/phone/CarrierConfigLoader.java
index c5b4875..18ff034 100644
--- a/src/com/android/phone/CarrierConfigLoader.java
+++ b/src/com/android/phone/CarrierConfigLoader.java
@@ -194,7 +194,7 @@
 
                 case EVENT_SYSTEM_UNLOCKED:
                 {
-                    for (int i = 0; i < TelephonyManager.from(mContext).getPhoneCount(); ++i) {
+                    for (int i = 0; i < TelephonyManager.from(mContext).getMaxPhoneCount(); ++i) {
                         // When user unlock device, we should only try to send broadcast again if we
                         // have sent it before unlock. This will avoid we try to load carrier config
                         // when SIM is still loading when unlock happens.
@@ -211,7 +211,7 @@
                     // Only update if there are cached config removed to avoid updating config for
                     // unrelated packages.
                     if (clearCachedConfigForPackage(carrierPackageName)) {
-                        int numPhones = TelephonyManager.from(mContext).getPhoneCount();
+                        int numPhones = TelephonyManager.from(mContext).getMaxPhoneCount();
                         for (int i = 0; i < numPhones; ++i) {
                             updateConfigForPhoneId(i);
                         }
@@ -523,7 +523,7 @@
         pkgFilter.addDataScheme("package");
         context.registerReceiver(mPackageReceiver, pkgFilter);
 
-        int numPhones = TelephonyManager.from(context).getPhoneCount();
+        int numPhones = TelephonyManager.from(context).getMaxPhoneCount();
         mConfigFromDefaultApp = new PersistableBundle[numPhones];
         mConfigFromCarrierApp = new PersistableBundle[numPhones];
         mOverrideConfigs = new PersistableBundle[numPhones];
@@ -566,6 +566,13 @@
             configPackagename = mPlatformCarrierConfigPackage;
             configToSend = mConfigFromDefaultApp[phoneId];
         }
+
+        // mOverrideConfigs is for testing. And it will override current configs.
+        PersistableBundle config = mOverrideConfigs[phoneId];
+        if (config != null) {
+            configToSend.putAll(config);
+        }
+
         mSubscriptionInfoUpdater.updateSubscriptionByCarrierConfigAndNotifyComplete(
                 phoneId, configPackagename, configToSend,
                 mHandler.obtainMessage(EVENT_SUBSCRIPTION_INFO_UPDATED, phoneId, -1));
diff --git a/src/com/android/phone/EmergencyCallbackModeExitDialog.java b/src/com/android/phone/EmergencyCallbackModeExitDialog.java
index 2492f46..dcfa024 100644
--- a/src/com/android/phone/EmergencyCallbackModeExitDialog.java
+++ b/src/com/android/phone/EmergencyCallbackModeExitDialog.java
@@ -68,6 +68,7 @@
     private boolean mInEmergencyCall = false;
     private static final int ECM_TIMER_RESET = 1;
     private Phone mPhone = null;
+    private boolean mIsResumed = false;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -100,6 +101,18 @@
     }
 
     @Override
+    public void onResume() {
+        super.onResume();
+        mIsResumed = true;
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        mIsResumed = false;
+    }
+
+    @Override
     public void onDestroy() {
         super.onDestroy();
         try {
@@ -176,7 +189,7 @@
      * Shows Emergency Callback Mode dialog and starts countdown timer
      */
     private void showEmergencyCallbackModeExitDialog() {
-        if (!this.isResumed()) {
+        if (!mIsResumed) {
             Log.w(TAG, "Tried to show dialog, but activity was already finished");
             return;
         }
diff --git a/src/com/android/phone/PhoneGlobals.java b/src/com/android/phone/PhoneGlobals.java
index 29fff0d..8094812 100644
--- a/src/com/android/phone/PhoneGlobals.java
+++ b/src/com/android/phone/PhoneGlobals.java
@@ -39,7 +39,6 @@
 import android.os.PowerManager;
 import android.os.SystemClock;
 import android.os.SystemProperties;
-import android.os.UpdateLock;
 import android.os.UserManager;
 import android.preference.PreferenceManager;
 import android.provider.Settings;
@@ -187,8 +186,6 @@
     private PowerManager.WakeLock mPartialWakeLock;
     private KeyguardManager mKeyguardManager;
 
-    private UpdateLock mUpdateLock;
-
     private int mDefaultDataSubId = SubscriptionManager.INVALID_SUBSCRIPTION_ID;
     private final LocalLog mDataRoamingNotifLog = new LocalLog(50);
 
@@ -347,12 +344,6 @@
 
             mKeyguardManager = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
 
-            // Get UpdateLock to suppress system-update related events (e.g. dialog show-up)
-            // during phone calls.
-            mUpdateLock = new UpdateLock("phone");
-
-            if (DBG) Log.d(LOG_TAG, "onCreate: mUpdateLock: " + mUpdateLock);
-
             // Create the CallerInfoCache singleton, which remembers custom ring tone and
             // send-to-voicemail settings.
             //
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index cd4509a..a847d66 100755
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -61,6 +61,7 @@
 import android.telecom.PhoneAccount;
 import android.telecom.PhoneAccountHandle;
 import android.telecom.TelecomManager;
+import android.telephony.Annotation.ApnType;
 import android.telephony.CarrierConfigManager;
 import android.telephony.CarrierRestrictionRules;
 import android.telephony.CellInfo;
@@ -92,7 +93,6 @@
 import android.telephony.VisualVoicemailSmsFilterSettings;
 import android.telephony.cdma.CdmaCellLocation;
 import android.telephony.data.ApnSetting;
-import android.telephony.data.ApnSetting.ApnType;
 import android.telephony.emergency.EmergencyNumber;
 import android.telephony.gsm.GsmCellLocation;
 import android.telephony.ims.ImsException;
@@ -2882,18 +2882,19 @@
         if (!SubscriptionManager.isValidSubscriptionId(subId)) {
             throw new IllegalArgumentException("Invalid Subscription ID: " + subId);
         }
-        Binder.withCleanCallingIdentity(() -> {
-            try {
-                // TODO: Refactor to remove ImsManager dependence and query through ImsPhone.
-                ImsManager.getInstance(mApp, getSlotIndexOrException(subId))
-                        .removeRegistrationCallbackForSubscription(c, subId);
-            } catch (ImsException e) {
-                Log.i(LOG_TAG, "unregisterImsRegistrationCallback: " + subId
-                        + "is inactive, ignoring unregister.");
-                // If the subscription is no longer active, just return, since the callback
-                // will already have been removed internally.
-            }
-        });
+        final long token = Binder.clearCallingIdentity();
+        try {
+            // TODO: Refactor to remove ImsManager dependence and query through ImsPhone.
+            ImsManager.getInstance(mApp, getSlotIndexOrException(subId))
+                    .removeRegistrationCallbackForSubscription(c, subId);
+        } catch (ImsException e) {
+            Log.i(LOG_TAG, "unregisterImsRegistrationCallback: " + subId
+                    + "is inactive, ignoring unregister.");
+            // If the subscription is no longer active, just return, since the callback
+            // will already have been removed internally.
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
     }
 
     @Override
@@ -2915,22 +2916,23 @@
     @Override
     public void unregisterMmTelCapabilityCallback(int subId, IImsCapabilityCallback c) {
         enforceReadPrivilegedPermission("unregisterMmTelCapabilityCallback");
-
         if (!SubscriptionManager.isValidSubscriptionId(subId)) {
             throw new IllegalArgumentException("Invalid Subscription ID: " + subId);
         }
-        Binder.withCleanCallingIdentity(() -> {
-            try {
-                // TODO: Refactor to remove ImsManager dependence and query through ImsPhone.
-                ImsManager.getInstance(mApp, getSlotIndexOrException(subId))
+
+        final long token = Binder.clearCallingIdentity();
+        try {
+            // TODO: Refactor to remove ImsManager dependence and query through ImsPhone.
+            ImsManager.getInstance(mApp, getSlotIndexOrException(subId))
                         .removeCapabilitiesCallbackForSubscription(c, subId);
-            } catch (ImsException e) {
-                Log.i(LOG_TAG, "unregisterMmTelCapabilityCallback: " + subId
-                        + "is inactive, ignoring unregister.");
-                // If the subscription is no longer active, just return, since the callback
-                // will already have been removed internally.
-            }
-        });
+        } catch (ImsException e) {
+            Log.i(LOG_TAG, "unregisterMmTelCapabilityCallback: " + subId
+                     + "is inactive, ignoring unregister.");
+             // If the subscription is no longer active, just return, since the callback
+             // will already have been removed internally.
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
     }
 
     @Override
diff --git a/src/com/android/services/telephony/EmergencyTonePlayer.java b/src/com/android/services/telephony/EmergencyTonePlayer.java
index 8e26349..431f8d7 100644
--- a/src/com/android/services/telephony/EmergencyTonePlayer.java
+++ b/src/com/android/services/telephony/EmergencyTonePlayer.java
@@ -23,7 +23,6 @@
 import android.media.AudioAttributes;
 import android.media.AudioManager;
 import android.media.ToneGenerator;
-import android.os.SystemVibrator;
 import android.os.Vibrator;
 import android.provider.Settings;
 
@@ -49,11 +48,9 @@
                 .setUsage(AudioAttributes.USAGE_VOICE_COMMUNICATION)
                 .build();
 
-    // We don't rely on getSystemService(Context.VIBRATOR_SERVICE) to make sure that this vibrator
-    // object will be isolated from others.
-    private final Vibrator mVibrator = new SystemVibrator();
     private final Context mContext;
     private final AudioManager mAudioManager;
+    private final Vibrator mVibrator;
 
     private ToneGenerator mToneGenerator;
     private int mSavedInCallVolume;
@@ -62,6 +59,7 @@
     EmergencyTonePlayer(Context context) {
         mContext = context;
         mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
+        mVibrator = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);
     }
 
     public void start() {
diff --git a/src/com/android/services/telephony/ImsConference.java b/src/com/android/services/telephony/ImsConference.java
index bf0374f..e14f422 100644
--- a/src/com/android/services/telephony/ImsConference.java
+++ b/src/com/android/services/telephony/ImsConference.java
@@ -847,7 +847,7 @@
             // If the single party call emulation fature flag is enabled, we can potentially treat
             // the conference as a single party call when there is just one participant.
             if (mFeatureFlagProxy.isUsingSinglePartyCallEmulation()) {
-                if (oldParticipantCount > 1 && newParticipantCount == 1) {
+                if (oldParticipantCount != 1 && newParticipantCount == 1) {
                     // If number of participants goes to 1, emulate a single party call.
                     startEmulatingSinglePartyCall();
                 } else if (mIsEmulatingSinglePartyCall && !isSinglePartyConference) {
@@ -1330,4 +1330,12 @@
         return isMaximumConferenceSizeEnforced()
                 && getNumberOfParticipants() >= getMaximumConferenceSize();
     }
+
+    /**
+     * @return {@code True} if the ImsConference is emulating single party call.
+     */
+    @VisibleForTesting
+    public boolean isEmulatingSinglePartyCall() {
+        return mIsEmulatingSinglePartyCall;
+    }
 }
diff --git a/src/com/android/services/telephony/RadioOnHelper.java b/src/com/android/services/telephony/RadioOnHelper.java
index 288c72c..85f94ab 100644
--- a/src/com/android/services/telephony/RadioOnHelper.java
+++ b/src/com/android/services/telephony/RadioOnHelper.java
@@ -53,7 +53,7 @@
             return;
         }
         mListeners = new ArrayList<>(2);
-        for (int i = 0; i < TelephonyManager.getDefault().getPhoneCount(); i++) {
+        for (int i = 0; i < TelephonyManager.getDefault().getMaxPhoneCount(); i++) {
             mListeners.add(new RadioOnStateListener());
         }
     }
@@ -76,7 +76,7 @@
         mCallback = callback;
         mInProgressListeners.clear();
         mIsRadioOnCallingEnabled = false;
-        for (int i = 0; i < TelephonyManager.getDefault().getPhoneCount(); i++) {
+        for (int i = 0; i < TelephonyManager.getDefault().getMaxPhoneCount(); i++) {
             Phone phone = PhoneFactory.getPhone(i);
             if (phone == null) {
                 continue;
diff --git a/src/com/android/services/telephony/TelephonyConnectionService.java b/src/com/android/services/telephony/TelephonyConnectionService.java
index 927b2c9..0e5a612 100644
--- a/src/com/android/services/telephony/TelephonyConnectionService.java
+++ b/src/com/android/services/telephony/TelephonyConnectionService.java
@@ -25,6 +25,9 @@
 import android.content.IntentFilter;
 import android.net.Uri;
 import android.os.Bundle;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Looper;
 import android.provider.Settings;
 import android.telecom.Conference;
 import android.telecom.Connection;
@@ -176,6 +179,8 @@
     // destroyed.
     @VisibleForTesting
     public Pair<WeakReference<TelephonyConnection>, Queue<Phone>> mEmergencyRetryCache;
+    private Handler mDdsSwitchHandler;
+    private HandlerThread mHandlerThread;
 
     /**
      * Keeps track of the status of a SIM slot.
@@ -329,11 +334,17 @@
         IntentFilter intentFilter = new IntentFilter(
                 TelecomManager.ACTION_TTY_PREFERRED_MODE_CHANGED);
         registerReceiver(mTtyBroadcastReceiver, intentFilter);
+
+        mHandlerThread = new HandlerThread("DdsSwitchHandlerThread");
+        mHandlerThread.start();
+        Looper looper = mHandlerThread.getLooper();
+        mDdsSwitchHandler = new Handler(looper);
     }
 
     @Override
     public boolean onUnbind(Intent intent) {
         unregisterReceiver(mTtyBroadcastReceiver);
+        mHandlerThread.quitSafely();
         return super.onUnbind(intent);
     }
 
@@ -523,14 +534,14 @@
             } else {
                 final Connection resultConnection = getTelephonyConnection(request, numberToDial,
                         true, handle, phone);
-                CompletableFuture<Boolean> phoneFuture = delayDialForDdsSwitch(phone);
-                phoneFuture.whenComplete((result, error) -> {
-                    if (error != null) {
-                        Log.w(this, "onCreateOutgoingConn - delayDialForDdsSwitch exception= "
-                                + error.getMessage());
+                mDdsSwitchHandler.post(new Runnable() {
+                    @Override
+                    public void run() {
+                        boolean result = delayDialForDdsSwitch(phone);
+                        Log.i(this,
+                                "onCreateOutgoingConn - delayDialForDdsSwitch result = " + result);
+                        placeOutgoingConnection(request, resultConnection, phone);
                     }
-                    Log.i(this, "onCreateOutgoingConn - delayDialForDdsSwitch result = " + result);
-                    placeOutgoingConnection(request, resultConnection, phone);
                 });
                 return resultConnection;
             }
@@ -604,14 +615,14 @@
                 adjustAndPlaceOutgoingConnection(phone, originalConnection, request, numberToDial,
                         handle, originalPhoneType, false);
             } else {
-                delayDialForDdsSwitch(phone).whenComplete((result, error) -> {
-                    if (error != null) {
-                        Log.w(this, "handleOnComplete - delayDialForDdsSwitch exception= "
-                                + error.getMessage());
+                mDdsSwitchHandler.post(new Runnable() {
+                    @Override
+                    public void run() {
+                        boolean result = delayDialForDdsSwitch(phone);
+                        Log.i(this, "handleOnComplete - delayDialForDdsSwitch result = " + result);
+                        adjustAndPlaceOutgoingConnection(phone, originalConnection, request,
+                                numberToDial, handle, originalPhoneType, true);
                     }
-                    Log.i(this, "handleOnComplete - delayDialForDdsSwitch result = " + result);
-                    adjustAndPlaceOutgoingConnection(phone, originalConnection, request,
-                            numberToDial, handle, originalPhoneType, true);
                 });
             }
 
@@ -1234,6 +1245,11 @@
         com.android.internal.telephony.Connection originalConnection = null;
         try {
             if (phone != null) {
+                EmergencyNumber emergencyNumber =
+                        phone.getEmergencyNumberTracker().getEmergencyNumber(number);
+                if (emergencyNumber != null) {
+                    phone.notifyOutgoingEmergencyCall(emergencyNumber);
+                }
                 originalConnection = phone.dial(number, new ImsPhone.ImsDialArgs.Builder()
                         .setVideoState(videoState)
                         .setIntentExtras(extras)
@@ -1375,13 +1391,22 @@
         return chosenPhone;
     }
 
-    private CompletableFuture<Boolean> delayDialForDdsSwitch(Phone phone) {
+    /**
+     * If needed, block until the the default data is is switched for outgoing emergency call, or
+     * timeout expires.
+     */
+    private boolean delayDialForDdsSwitch(Phone phone) {
         if (phone == null) {
-            return CompletableFuture.completedFuture(Boolean.TRUE);
+            return true;
         }
-        return possiblyOverrideDefaultDataForEmergencyCall(phone)
-                .completeOnTimeout(false, DEFAULT_DATA_SWITCH_TIMEOUT_MS,
-                        TimeUnit.MILLISECONDS);
+        try {
+            return possiblyOverrideDefaultDataForEmergencyCall(phone).get(
+                    DEFAULT_DATA_SWITCH_TIMEOUT_MS, TimeUnit.MILLISECONDS);
+        } catch (Exception e) {
+            Log.w(this, "onCreateOutgoingConn - delayDialForDdsSwitch exception= "
+                    + e.getMessage());
+            return false;
+        }
     }
 
     /**
diff --git a/tests/src/com/android/services/telephony/ImsConferenceTest.java b/tests/src/com/android/services/telephony/ImsConferenceTest.java
index eaec5b6..6f8b3e8 100644
--- a/tests/src/com/android/services/telephony/ImsConferenceTest.java
+++ b/tests/src/com/android/services/telephony/ImsConferenceTest.java
@@ -16,19 +16,16 @@
 
 package com.android.services.telephony;
 
-import static org.mockito.Matchers.eq;
-import static org.mockito.Mockito.doAnswer;
-import static org.mockito.Mockito.doNothing;
-import static org.mockito.Mockito.never;
-import static org.mockito.Mockito.reset;
-import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.when;
-import static org.mockito.Mockito.any;
-import static org.mockito.Mockito.times;
-
-import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.reset;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
 
 import android.net.Uri;
 import android.os.Looper;
@@ -39,15 +36,10 @@
 import android.telecom.PhoneAccountHandle;
 import android.test.suitebuilder.annotation.SmallTest;
 
-import com.android.internal.telephony.PhoneConstants;
-
 import org.junit.Before;
 import org.junit.Test;
-
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
-import org.mockito.invocation.InvocationOnMock;
-import org.mockito.stubbing.Answer;
 
 import java.util.Arrays;
 
@@ -362,6 +354,31 @@
     }
 
     /**
+     * Verify that the single party emulate correctly when the conference start with only
+     * one participant.
+     */
+    @Test
+    @SmallTest
+    public void testSinglePartyEmulationWithOneParticipantAtBeginning() {
+        when(mMockTelecomAccountRegistry.isUsingSimCallManager(any(PhoneAccountHandle.class)))
+                .thenReturn(false);
+
+        ImsConference imsConference = new ImsConference(mMockTelecomAccountRegistry,
+                mMockTelephonyConnectionServiceProxy, mConferenceHost,
+                null /* phoneAccountHandle */, () -> true /* featureFlagProxy */);
+
+        ConferenceParticipant participant1 = new ConferenceParticipant(
+                Uri.parse("tel:6505551212"),
+                "A",
+                Uri.parse("sip:6505551212@testims.com"),
+                Connection.STATE_ACTIVE,
+                Call.Details.DIRECTION_INCOMING);
+        imsConference.handleConferenceParticipantsUpdate(mConferenceHost,
+                Arrays.asList(participant1));
+        assertTrue(imsConference.isEmulatingSinglePartyCall());
+    }
+
+    /**
      * Verify that we do not use single party emulation when a sim call manager is in use.
      */
     @Test