diff --git a/CHANGES.md b/CHANGES.md
index d6bcacef5..a2cb957f1 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,18 @@
+Synapse 1.77.0rc2 (2023-02-10)
+==============================
+
+Bugfixes
+--------
+
+- Fix bug where retried replication requests would return a failure. Introduced in v1.76.0. ([\#15024](https://github.com/matrix-org/synapse/issues/15024))
+
+
+Internal Changes
+----------------
+
+- Prepare for future database schema changes. ([\#15036](https://github.com/matrix-org/synapse/issues/15036))
+
+
 Synapse 1.77.0rc1 (2023-02-07)
 ==============================
 
diff --git a/debian/changelog b/debian/changelog
index becc41c12..461953742 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.77.0~rc2) stable; urgency=medium
+
+  * New Synapse release 1.77.0rc2.
+
+ -- Synapse Packaging team <packages@matrix.org>  Fri, 10 Feb 2023 12:44:21 +0000
+
 matrix-synapse-py3 (1.77.0~rc1) stable; urgency=medium
 
   * New Synapse release 1.77.0rc1.
diff --git a/pyproject.toml b/pyproject.toml
index 2a21da635..21621510c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -89,7 +89,7 @@ manifest-path = "rust/Cargo.toml"
 
 [tool.poetry]
 name = "matrix-synapse"
-version = "1.77.0rc1"
+version = "1.77.0rc2"
 description = "Homeserver for the Matrix decentralised comms protocol"
 authors = ["Matrix.org Team and Contributors <packages@matrix.org>"]
 license = "Apache-2.0"
diff --git a/synapse/replication/http/_base.py b/synapse/replication/http/_base.py
index 908f3f1db..c20d9c7e9 100644
--- a/synapse/replication/http/_base.py
+++ b/synapse/replication/http/_base.py
@@ -426,6 +426,8 @@ class ReplicationEndpoint(metaclass=abc.ABCMeta):
             code, response = await self.response_cache.wrap(
                 txn_id, self._handle_request, request, content, **kwargs
             )
+            # Take a copy so we don't mutate things in the cache.
+            response = dict(response)
         else:
             # The `@cancellable` decorator may be applied to `_handle_request`. But we
             # told `HttpServer.register_paths` that our handler is `_check_auth_and_handle`,
diff --git a/synapse/storage/schema/__init__.py b/synapse/storage/schema/__init__.py
index 19dbf2da7..d3103a6c7 100644
--- a/synapse/storage/schema/__init__.py
+++ b/synapse/storage/schema/__init__.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-SCHEMA_VERSION = 73  # remember to update the list below when updating
+SCHEMA_VERSION = 74  # remember to update the list below when updating
 """Represents the expectations made by the codebase about the database schema
 
 This should be incremented whenever the codebase changes its requirements on the
@@ -78,7 +78,7 @@ Changes in SCHEMA_VERSION = 72:
     - Unused column application_services_state.last_txn is dropped
     - Cache invalidation stream id sequence now begins at 2 to match code expectation.
 
-Changes in SCHEMA_VERSION = 73;
+Changes in SCHEMA_VERSION = 73:
     - thread_id column is added to event_push_actions, event_push_actions_staging
       event_push_summary, receipts_linearized, and receipts_graph.
     - Add table `event_failed_pull_attempts` to keep track when we fail to pull
@@ -86,6 +86,11 @@ Changes in SCHEMA_VERSION = 73;
     - Add indexes to various tables (`event_failed_pull_attempts`, `insertion_events`,
       `batch_events`) to make it easy to delete all associated rows when purging a room.
     - `inserted_ts` column is added to `event_push_actions_staging` table.
+
+Changes in SCHEMA_VERSION = 74:
+    - A query on `event_stream_ordering` column has now been disambiguated (i.e. the
+      codebase can handle the `current_state_events`, `local_current_memberships` and
+      `room_memberships` tables having an `event_stream_ordering` column).
 """