diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/storage/MessagesDynamoDb.java b/service/src/main/java/org/whispersystems/textsecuregcm/storage/MessagesDynamoDb.java
index 46f1c068..deec76ea 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/storage/MessagesDynamoDb.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/storage/MessagesDynamoDb.java
@@ -26,6 +26,8 @@ import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutorService;
 import java.util.function.Predicate;
+import java.util.stream.Stream;
+
 import org.reactivestreams.Publisher;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -135,7 +137,14 @@ public class MessagesDynamoDb extends AbstractDynamoDbStore {
   }
 
   public Publisher<MessageProtos.Envelope> load(final UUID destinationAccountUuid, final Device device, final Integer limit) {
-    final AttributeValue partitionKey = convertPartitionKey(destinationAccountUuid, device);
+    return Flux.concat(
+        Stream.of(convertPartitionKeyDeprecated(destinationAccountUuid, device), convertPartitionKey(destinationAccountUuid, device))
+            .distinct()
+            .map(pk -> load(limit, pk))
+            .toList());
+  }
+
+  public Publisher<MessageProtos.Envelope> load(final Integer limit, final AttributeValue partitionKey) {
     QueryRequest.Builder queryRequestBuilder = QueryRequest.builder()
         .tableName(tableName)
         .consistentRead(true)
@@ -165,7 +174,19 @@ public class MessagesDynamoDb extends AbstractDynamoDbStore {
 
   public CompletableFuture<Optional<MessageProtos.Envelope>> deleteMessageByDestinationAndGuid(
       final UUID destinationAccountUuid, final Device destinationDevice, final UUID messageUuid) {
-    final AttributeValue partitionKey = convertPartitionKey(destinationAccountUuid, destinationDevice);
+    return Stream.of(convertPartitionKey(destinationAccountUuid, destinationDevice),
+        convertPartitionKeyDeprecated(destinationAccountUuid, destinationDevice))
+        .distinct()
+        .map(pk -> deleteMessageByDestinationAndGuid(pk, messageUuid))
+        // this combines the futures by producing a future that returns an arbitrary nonempty
+        // result if there is one, which should be OK because only one of the keys
+        // should produce a nonempty result for any given message uuid
+        .reduce((f, g) -> f.thenCombine(g, (a, b) -> a.or(() -> b)))
+        .get();
+  }
+
+  public CompletableFuture<Optional<MessageProtos.Envelope>> deleteMessageByDestinationAndGuid(
+      final AttributeValue partitionKey, final UUID messageUuid) {
     final QueryRequest queryRequest = QueryRequest.builder()
         .tableName(tableName)
         .indexName(LOCAL_INDEX_MESSAGE_UUID_NAME)
@@ -207,7 +228,18 @@ public class MessagesDynamoDb extends AbstractDynamoDbStore {
 
   public CompletableFuture<Optional<MessageProtos.Envelope>> deleteMessage(final UUID destinationAccountUuid,
       final Device destinationDevice, final UUID messageUuid, final long serverTimestamp) {
-    final AttributeValue partitionKey = convertPartitionKey(destinationAccountUuid, destinationDevice);
+    return Stream.of(convertPartitionKey(destinationAccountUuid, destinationDevice),
+        convertPartitionKeyDeprecated(destinationAccountUuid, destinationDevice))
+        .distinct()
+        .map(pk -> deleteMessage(pk, destinationDevice, messageUuid, serverTimestamp))
+        // this combines the futures by producing a future that returns an arbitrary nonempty
+        // result if there is one, which should be OK because only one of the keys
+        // should produce a nonempty result for any given message uuid
+        .reduce((f, g) -> f.thenCombine(g, (a, b) -> a.or(() -> b)))
+        .get();
+  }
+
+  public CompletableFuture<Optional<MessageProtos.Envelope>> deleteMessage(final AttributeValue partitionKey, final Device destinationDevice, final UUID messageUuid, final long serverTimestamp) {
     final AttributeValue sortKey = convertSortKey(destinationDevice.getId(), serverTimestamp, messageUuid);
     DeleteItemRequest.Builder deleteItemRequest = DeleteItemRequest.builder()
         .tableName(tableName)
@@ -247,6 +279,14 @@ public class MessagesDynamoDb extends AbstractDynamoDbStore {
     return AttributeValues.fromByteBuffer(byteBuffer.flip());
   }
 
+  private static AttributeValue convertPartitionKeyDeprecated(final UUID destinationAccountUuid, final Device destinationDevice) {
+    final ByteBuffer byteBuffer = ByteBuffer.allocate(24);
+    byteBuffer.putLong(destinationAccountUuid.getMostSignificantBits());
+    byteBuffer.putLong(destinationAccountUuid.getLeastSignificantBits());
+    byteBuffer.putLong(destinationDevice.getCreated() & ~0x7f + destinationDevice.getId());
+    return AttributeValues.fromByteBuffer(byteBuffer.flip());
+  }
+
   private static AttributeValue convertSortKey(final byte destinationDeviceId, final long serverTimestamp, final UUID messageUuid) {
     final ByteBuffer byteBuffer = ByteBuffer.allocate(24);
     byteBuffer.putLong(serverTimestamp);