diff --git a/app/src/main/java/org/unifiedpush/distributor/nextpush/AppCompanion.kt b/app/src/main/java/org/unifiedpush/distributor/nextpush/AppCompanion.kt
index 5f7ad4e..5918bdd 100644
--- a/app/src/main/java/org/unifiedpush/distributor/nextpush/AppCompanion.kt
+++ b/app/src/main/java/org/unifiedpush/distributor/nextpush/AppCompanion.kt
@@ -26,6 +26,9 @@ object AppCompanion {
     /** Have we received the start event ? To check the reverse proxy timeout is high enough */
     val started = AtomicBoolean(false)
 
+    /** Count messages since restart */
+    val messageCounter = AtomicInteger(0)
+
     /** Have we received the ping event ? To check the reverse proxy timeout is high enough */
     val pinged = AtomicBoolean(false)
     val bufferedResponseChecked = AtomicBoolean(false)
diff --git a/app/src/main/java/org/unifiedpush/distributor/nextpush/api/SSEListener.kt b/app/src/main/java/org/unifiedpush/distributor/nextpush/api/SSEListener.kt
index f710ddb..b8dbd4a 100644
--- a/app/src/main/java/org/unifiedpush/distributor/nextpush/api/SSEListener.kt
+++ b/app/src/main/java/org/unifiedpush/distributor/nextpush/api/SSEListener.kt
@@ -55,6 +55,7 @@ class SSEListener(val context: Context) : EventSourceListener() {
             when (type) {
                 "start" -> {
                     AppCompanion.started.set(true)
+                    AppCompanion.messageCounter.set(0)
                     StartingTimer.stop()
                     AppCompanion.bufferedResponseChecked.set(true)
                     NoStartNotification(context).delete()
@@ -80,6 +81,7 @@ class SSEListener(val context: Context) : EventSourceListener() {
                 }
 
                 "message" -> {
+                    AppCompanion.messageCounter.incrementAndGet()
                     val message = Gson().fromJson(data, SSEResponse::class.java)
                     sendMessage(
                         context,
diff --git a/app/src/main/java/org/unifiedpush/distributor/nextpush/services/FailureCounter.kt b/app/src/main/java/org/unifiedpush/distributor/nextpush/services/FailureCounter.kt
index e3c4332..fca8bcc 100644
--- a/app/src/main/java/org/unifiedpush/distributor/nextpush/services/FailureCounter.kt
+++ b/app/src/main/java/org/unifiedpush/distributor/nextpush/services/FailureCounter.kt
@@ -95,12 +95,14 @@ object FailureCounter {
     /**
      * Set the counter of failed events to 1.
      *
-     * Used when there is no Internet access.
+     * Used when there is no Internet access, or we want to restart the sync request to ack messages.
+     *
+     * The eventSource isn't closed, else it would call _onFailure_ and try to restart, which will
+     * be redundant
      */
     fun setFailOnce() {
         Log.d(TAG, "setFailOnce")
         Atomics.nFails.set(1)
-        Atomics.eventSource.getAndSet(null)?.cancel()
     }
 
     fun clearFails() {
diff --git a/app/src/main/java/org/unifiedpush/distributor/nextpush/services/RestartWorker.kt b/app/src/main/java/org/unifiedpush/distributor/nextpush/services/RestartWorker.kt
index 65ca986..233c483 100644
--- a/app/src/main/java/org/unifiedpush/distributor/nextpush/services/RestartWorker.kt
+++ b/app/src/main/java/org/unifiedpush/distributor/nextpush/services/RestartWorker.kt
@@ -11,9 +11,6 @@ import org.unifiedpush.distributor.nextpush.AppCompanion
 import org.unifiedpush.distributor.nextpush.account.AccountFactory.getAccount
 import org.unifiedpush.distributor.nextpush.utils.TAG
 
-private const val UNIQUE_PERIODIC_WORK_TAG = "nextpush::RestartWorker::unique_periodic"
-private const val UNIQUE_ONETIME_WORK_TAG = "nextpush::RestartWorker::unique_onetime"
-
 class RestartWorker(ctx: Context, params: WorkerParameters) : Worker(ctx, params) {
 
     /**
@@ -35,8 +32,21 @@ class RestartWorker(ctx: Context, params: WorkerParameters) : Worker(ctx, params
                 restartDate.time = it.time
                 restartDate.add(Calendar.SECOND, AppCompanion.keepalive.get())
                 Log.d(TAG, "restartDate: ${restartDate.time}")
-                if (currentDate.after(restartDate)) {
-                    Log.d(TAG, "We should have received an event before ${restartDate.time}. Restarting")
+
+                /**
+                 * We restart the service when:
+                 * - we didn't receive the last ping
+                 * - we have received more than [MAX_MSG] messages, so the received messages can be ack to the server
+                 * and deleted from the server
+                 */
+                val timeoutExpire = currentDate.after(restartDate)
+                val msgCount = AppCompanion.messageCounter.get()
+                if (timeoutExpire || msgCount > MAX_MSG) {
+                    if (timeoutExpire) {
+                        Log.d(TAG, "We should have received an event before ${restartDate.time}. Restarting")
+                    } else {
+                        Log.d(TAG, "Restarting to acknowledge $msgCount messages.")
+                    }
                     /**
                      * If there is at least one failure, we do not update [FailureCounter]'s counter,
                      * it will be done by the next requests.
@@ -61,6 +71,15 @@ class RestartWorker(ctx: Context, params: WorkerParameters) : Worker(ctx, params
 
     companion object {
         private val lock = Object()
+        private const val UNIQUE_PERIODIC_WORK_TAG = "nextpush::RestartWorker::unique_periodic"
+        private const val UNIQUE_ONETIME_WORK_TAG = "nextpush::RestartWorker::unique_onetime"
+
+        /**
+         * Number of messages before restarting the service to acknowledge to the server received messages.
+         *
+         * 256 messages means a _maximum_ of 1MB of ack messages (if all of them are 4kB)
+         */
+        private const val MAX_MSG = 256
 
         fun startPeriodic(context: Context) {
             getAccount(context) ?: return