diff --git a/CHANGES.md b/CHANGES.md
index 3bb00b6cea037b13b14722fe5bd27d6255eb068b..f0d3db78498fd5c987eeedf9561b7f2e9c26ccc6 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,19 @@
 Synapse 1.67.0rc1 (2022-09-06)
 ==============================
 
+This release removes using the deprecated direct TCP replication configuration
+for workers. Server admins should use Redis instead. See the [upgrade
+notes](https://matrix-org.github.io/synapse/v1.67/upgrade.html#upgrading-to-v1670).
+
+The minimum version of `poetry` supported for managing source checkouts is now
+1.2.0.
+
+Notice: from the next major release (v1.68.0) installing Synapse from a source
+checkout will require a recent Rust compiler. Those using packages or
+`pip install matrix-synapse` will not be affected. See the [upgrade
+notes](https://matrix-org.github.io/synapse/v1.67/upgrade.html#upgrading-to-v1670).
+
+
 Features
 --------
 
diff --git a/docs/upgrade.md b/docs/upgrade.md
index c6219d06e8b6b56c899f1de12c0572cd3277f26e..023ca0a30bdc08c18893a6e2b902cab07ea73955 100644
--- a/docs/upgrade.md
+++ b/docs/upgrade.md
@@ -111,6 +111,15 @@ and remove the TCP `replication` listener from config of the master and
 The minimum supported version of poetry is now 1.2. This should only affect
 those installing from a source checkout.
 
+## Rust requirement in the next release
+
+From the next major release (v1.68.0) installing Synapse from a source checkout
+will require a recent Rust compiler. Those using packages or
+`pip install matrix-synapse` will not be affected.
+
+The simplest way of installing Rust is via [rustup.rs](https://rustup.rs/)
+
+
 # Upgrading to v1.66.0
 
 ## Delegation of email validation no longer supported