Fixup changelog

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5b4d697..8d36fe6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md

@@ -1,3 +1,7 @@
+# Unreleased
+
+- Declare support for Python 3.12. Patch by Jelle Zijlstra.
+
 # Release 4.6.3 (June 1, 2023)
 
 - Fix a regression introduced in v4.6.0 in the implementation of
@@ -13,7 +17,6 @@
 - Skip a problematic test on Python 3.12.0b1. The test fails on 3.12.0b1 due to
   a bug in CPython, which will be fixed in 3.12.0b2. The
   `typing_extensions` test suite now passes on 3.12.0b1.
-- Declare support for Python 3.12. Patch by Jelle Zijlstra.
 
 # Release 4.6.2 (May 25, 2023)