diff --git a/changelogs/4.12.md b/changelogs/4.12.md
index ab233e6ca..ab96c2082 100644
--- a/changelogs/4.12.md
+++ b/changelogs/4.12.md
@@ -69,4 +69,27 @@ Released 9th January 2023.
 
 ## Fixes
 - Fixed players getting kicked during PvP.
-- Fixed players randomly getting kicked on Windows (improper rate limit handling wrt. 15ms timer resolution).
\ No newline at end of file
+- Fixed players randomly getting kicked on Windows (improper rate limit handling wrt. 15ms timer resolution).
+
+# 4.12.9
+Released 16th January 2023.
+
+## Improvements
+### Timings
+- Added new timers:
+  - `Server Mid-Tick Processing` - time spent processing Snooze interrupts between ticks (e.g. incoming network packets)
+  - `Server Tick Update Cycle` - time spent processing regular per-tick updates (e.g. entity movement, world updates, etc.) (`Server->tick()`)
+- `Full Server Tick` timer now counts the total of `Server Mid-Tick Processing` and `Server Tick Update Cycle`, which generates more accurate performance metrics.
+  - Previously, this timer only counted the time spent during regular per-tick updates, and the time recorded by `Server Mid-Tick Processing` was not included in the report at all.
+
+## Fixes
+- Fixed blocks such as pressure plates being able to be placed without the correct supporting blocks if the clicked block was solid.
+- Pressure plates now self-destruct when the block below them is removed.
+- Fixed being unable to place blocks by clicking on the side of a bell (when the click doesn't result in ringing the bell).
+- Fixed various rotation-aware blocks (e.g. stairs) behaving incorrectly when placed by clicking on the side of a replaceable block (e.g. tall grass).
+- Fixed banners being able to be placed on top of blocks such as skulls.
+- Fixed server-side collision boxes of walls and glass (which should connect, but didn't). Note that wall connections still don't show client side - this just fixes the collision boxes.
+- Fixed `PlayerInteractEvent` with `LEFT_CLICK` sometimes firing before `BlockBreakEvent` when breaking blocks.
+
+## Other changes
+- Increased packet batch budget for player sessions.
diff --git a/src/VersionInfo.php b/src/VersionInfo.php
index 90e4b50d0..95eee9e4a 100644
--- a/src/VersionInfo.php
+++ b/src/VersionInfo.php
@@ -32,7 +32,7 @@ use function str_repeat;
 final class VersionInfo{
 	public const NAME = "PocketMine-MP";
 	public const BASE_VERSION = "4.12.9";
-	public const IS_DEVELOPMENT_BUILD = true;
+	public const IS_DEVELOPMENT_BUILD = false;
 	public const BUILD_CHANNEL = "stable";
 
 	private function __construct(){