--- a/mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/uploaders/BatchingUploader.java
+++ b/mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/uploaders/BatchingUploader.java
@@ -123,17 +123,17 @@ public class BatchingUploader {
         this.executor = workQueue;
     }
 
     // Called concurrently from the threads running off of a record consumer thread pool.
     public void process(final Record record) {
         final String guid = record.guid;
 
         // If store failed entirely, just bail out. We've already told our delegate that we failed.
-        if (payloadDispatcher.storeFailed) {
+        if (payloadDispatcher.storeFailed.get()) {
             return;
         }
 
         // If a record or a payload failed, we won't let subsequent requests proceed.
         // This means that we may bail much earlier.
         if (payloadDispatcher.recordUploadFailed) {
             sessionStoreDelegate.deferredStoreDelegate(executor).onRecordStoreFailed(
                     new Server15PreviousPostFailedException(), guid

--- a/mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/uploaders/PayloadDispatcher.java
+++ b/mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/uploaders/PayloadDispatcher.java
@@ -10,16 +10,17 @@ import android.support.annotation.Visibl
 import org.mozilla.gecko.background.common.log.Logger;
 import org.mozilla.gecko.sync.CollectionConcurrentModificationException;
 import org.mozilla.gecko.sync.Server15RecordPostFailedException;
 import org.mozilla.gecko.sync.net.SyncResponse;
 import org.mozilla.gecko.sync.net.SyncStorageResponse;
 
 import java.util.ArrayList;
 import java.util.concurrent.Executor;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicLong;
 
 /**
  * Dispatches payload runnables and handles their results.
  *
  * All of the methods, except for `queue` and `finalizeQueue`, will be called from the thread(s)
  * running sequentially on the SingleThreadExecutor `executor`.
  */
@@ -33,17 +34,17 @@ class PayloadDispatcher {
 
     private final Executor executor;
     private final BatchingUploader uploader;
 
     // For both of these flags:
     // Written from sequentially running thread(s) on the SingleThreadExecutor `executor`.
     // Read by many threads running concurrently on the records consumer thread pool.
     volatile boolean recordUploadFailed = false;
-    volatile boolean storeFailed = false;
+    final AtomicBoolean storeFailed = new AtomicBoolean(false);
 
     PayloadDispatcher(Executor executor, BatchingUploader uploader, @Nullable Long initialLastModified) {
         // Initially we don't know if we're in a batching mode.
         this.batchWhiteboard = new BatchMeta(initialLastModified, null);
         this.uploader = uploader;
         this.executor = executor;
     }
 
@@ -100,17 +101,17 @@ class PayloadDispatcher {
         // If this was our very last commit, we're done storing records.
         // Get Last-Modified timestamp from the response, and pass it upstream.
         if (isLastPayload) {
             uploader.finished();
         }
     }
 
     void lastPayloadFailed(Exception e) {
-        uploader.sessionStoreDelegate.onStoreFailed(e);
+        doStoreFailed(e);
     }
 
     void finalizeQueue(final boolean needToCommit, final Runnable finalRunnable) {
         executor.execute(new NonPayloadContextRunnable() {
             @Override
             public void run() {
                 // Must be called after last payload upload finishes.
                 if (needToCommit && Boolean.TRUE.equals(batchWhiteboard.getInBatchingMode())) {
@@ -130,25 +131,31 @@ class PayloadDispatcher {
 
     void recordFailed(final Exception e, final String recordGuid) {
         Logger.debug(LOG_TAG, "Record store failed for guid " + recordGuid + " with exception: " + e.toString());
         recordUploadFailed = true;
         uploader.sessionStoreDelegate.onRecordStoreFailed(e, recordGuid);
     }
 
     void concurrentModificationDetected() {
-        recordUploadFailed = true;
-        storeFailed = true;
-        uploader.sessionStoreDelegate.onStoreFailed(new CollectionConcurrentModificationException());
+        doStoreFailed(new CollectionConcurrentModificationException());
     }
 
     void prepareForNextBatch() {
         batchWhiteboard = batchWhiteboard.nextBatchMeta();
     }
 
+    private void doStoreFailed(Exception reason) {
+        if (storeFailed.getAndSet(true)) {
+            return;
+        }
+        recordUploadFailed = true;
+        uploader.sessionStoreDelegate.onStoreFailed(reason);
+    }
+
     private static void bumpTimestampTo(final AtomicLong current, long newValue) {
         while (true) {
             long existing = current.get();
             if (existing > newValue) {
                 return;
             }
             if (current.compareAndSet(existing, newValue)) {
                 return;

--- a/mobile/android/tests/background/junit4/src/org/mozilla/gecko/sync/repositories/uploaders/PayloadUploadDelegateTest.java
+++ b/mobile/android/tests/background/junit4/src/org/mozilla/gecko/sync/repositories/uploaders/PayloadUploadDelegateTest.java
@@ -431,17 +431,17 @@ public class PayloadUploadDelegateTest {
         PayloadUploadDelegate payloadUploadDelegate = new PayloadUploadDelegate(authHeaderProvider, payloadDispatcher, postedGuids, false, false);
 
         final HttpResponse response = new BasicHttpResponse(
                 new BasicStatusLine(new ProtocolVersion("HTTP", 1, 1), 412, "Precondition failed"));
         payloadUploadDelegate.handleRequestFailure(new SyncStorageResponse(response));
 
         assertEquals(0, ((MockPayloadDispatcher) payloadDispatcher).failedRecords.size());
         assertTrue(payloadDispatcher.recordUploadFailed);
-        assertTrue(payloadDispatcher.storeFailed);
+        assertTrue(payloadDispatcher.storeFailed.get());
 
         assertTrue(((MockRepositorySessionStoreDelegate) sessionStoreDelegate).storeFailedException instanceof CollectionConcurrentModificationException);
     }
 
     @Test
     public void testIfUnmodifiedSinceNoLM() {
         PayloadUploadDelegate payloadUploadDelegate = new PayloadUploadDelegate(
                 authHeaderProvider, payloadDispatcher, new ArrayList<String>(), false, false);