Add updated primary announce content.

This needs to be fixed in galaxy-release-util; by default updating this
is skipped, but it'll hold the previous announcement placeholder.
Should detect placeholder and overwrite if it's there.

doc/source/releases/23.2_announce.rst

@@ -1,12 +1,45 @@
 
-:orphan:
-
 ===========================================================
 October 2023 Galaxy Release (v 23.2)
 ===========================================================
 
+.. include:: _header.rst
+
+Highlights
+===========================================================
+
+**Feature1**
+  Feature description.
+
+**Feature2**
+  Feature description.
+
+**Feature3**
+  Feature description.
+
+Also check out the `23.2 user release notes <23.2_announce_user.html>`__
+
+Get Galaxy
+==========
 
-Schedule
+The code lives at `GitHub <https://github.com/galaxyproject/galaxy>`__ and you should have `Git <https://git-scm.com/>`__ to obtain it.
+
+To get a new Galaxy repository run:
+  .. code-block:: shell
+
+      $ git clone -b release_23.2 https://github.com/galaxyproject/galaxy.git
+
+To update an existing Galaxy repository run:
+  .. code-block:: shell
+
+      $ git fetch origin && git checkout release_23.2 && git pull --ff-only origin release_23.2
+
+See the `community hub <https://galaxyproject.org/develop/source-code/>`__ for additional details on source code locations.
+
+Release Notes
 ===========================================================
- * Planned Freeze Date: 2023-10-02
- * Planned Release Date: 2023-10-23
+
+.. include:: 23.2.rst
+   :start-after: announce_start
+
+.. include:: _thanks.rst