diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1271ace2..654be26d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,10 @@ All notable changes to this project will be documented in this file. The format
 - **SpamAssassin:**
   - Removed Pyzor + Razor due to maintenance concerns. From observations it is unlikely to have any notable regression ([#4548](https://github.com/docker-mailserver/docker-mailserver/pull/4548))
 
+### Updated
+- **APT**
+  - Updated `.list` => `.sources` according to the new [DEB822](https://repolib.readthedocs.io/en/latest/deb822-format.html) format ([#4556](https://github.com/docker-mailserver/docker-mailserver/pull/4556))
+
 ## [v15.1.0](https://github.com/docker-mailserver/docker-mailserver/compare/v15.1.0...HEAD)
 
 > [!NOTE]