diff --git a/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/firestore/FirestoreV1WriteFn.java b/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/firestore/FirestoreV1WriteFn.java
index 70c2b91ffbfd..6bbb00e76f2d 100644
--- a/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/firestore/FirestoreV1WriteFn.java
+++ b/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/firestore/FirestoreV1WriteFn.java
@@ -51,6 +51,7 @@
 import org.apache.beam.sdk.transforms.display.DisplayData;
 import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
 import org.apache.beam.sdk.util.BackOffUtils;
+import org.apache.beam.sdk.util.Preconditions;
 import org.apache.beam.sdk.values.KV;
 import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.annotations.VisibleForTesting;
 import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableList;
@@ -87,7 +88,6 @@ static final class BatchWriteFnWithSummary extends BaseBatchWriteFn<WriteSuccess
     @Override
     void handleWriteFailures(
         ContextAdapter<WriteSuccessSummary> context,
-        Instant timestamp,
         List<KV<WriteFailure, BoundedWindow>> writeFailures,
         Runnable logMessage) {
       throw new FailedWritesException(
@@ -125,12 +125,11 @@ static final class BatchWriteFnWithDeadLetterQueue extends BaseBatchWriteFn<Writ
     @Override
     void handleWriteFailures(
         ContextAdapter<WriteFailure> context,
-        Instant timestamp,
         List<KV<WriteFailure, BoundedWindow>> writeFailures,
         Runnable logMessage) {
       logMessage.run();
       for (KV<WriteFailure, BoundedWindow> kv : writeFailures) {
-        context.output(kv.getKey(), timestamp, kv.getValue());
+        context.output(kv.getKey(), kv.getValue().maxTimestamp(), kv.getValue());
       }
     }
 
@@ -274,7 +273,6 @@ public void processElement(ProcessContext context, BoundedWindow window) throws
                 getWriteType(write), getName(write));
         handleWriteFailures(
             contextAdapter,
-            clock.instant(),
             ImmutableList.of(
                 KV.of(
                     new WriteFailure(
@@ -466,7 +464,7 @@ private DoFlushStatus doFlush(
         if (okCount == writesCount) {
           handleWriteSummary(
               context,
-              end,
+              Preconditions.checkArgumentNotNull(okWindow).maxTimestamp(),
               KV.of(new WriteSuccessSummary(okCount, okBytes), coerceNonNull(okWindow)),
               () ->
                   LOG.debug(
@@ -481,7 +479,6 @@ private DoFlushStatus doFlush(
             int finalOkCount = okCount;
             handleWriteFailures(
                 context,
-                end,
                 ImmutableList.copyOf(nonRetryableWrites),
                 () ->
                     LOG.warn(
@@ -506,7 +503,7 @@ private DoFlushStatus doFlush(
             if (okCount > 0) {
               handleWriteSummary(
                   context,
-                  end,
+                  Preconditions.checkArgumentNotNull(okWindow).maxTimestamp(),
                   KV.of(new WriteSuccessSummary(okCount, okBytes), coerceNonNull(okWindow)),
                   logMessage);
             } else {
@@ -542,7 +539,6 @@ private enum DoFlushStatus {
 
     abstract void handleWriteFailures(
         ContextAdapter<OutT> context,
-        Instant timestamp,
         List<KV<WriteFailure, BoundedWindow>> writeFailures,
         Runnable logMessage);