diff --git a/CHANGELOG.md b/CHANGELOG.md
index f658c2d85..67a493d9f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.3.1] - 2024-09-26
+
+### Fixed
+
+* PHP Warnings
+* PHPCS issues
+
 ## [3.3.0] - 2024-09-25
 
 ### Added
@@ -940,6 +947,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * initial
 
+[3.3.1]: https://github.com/Automattic/wordpress-activitypub/compare/3.3.0...3.3.1
 [3.3.0]: https://github.com/Automattic/wordpress-activitypub/compare/3.2.5...3.3.0
 [3.2.5]: https://github.com/Automattic/wordpress-activitypub/compare/3.2.4...3.2.5
 [3.2.4]: https://github.com/Automattic/wordpress-activitypub/compare/3.2.3...3.2.4
diff --git a/README.md b/README.md
index aadbdaa88..40cc758b5 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 **Tags:** OStatus, fediverse, activitypub, activitystream  
 **Requires at least:** 5.5  
 **Tested up to:** 6.6  
-**Stable tag:** 3.3.0  
+**Stable tag:** 3.3.1  
 **Requires PHP:** 7.0  
 **License:** MIT  
 **License URI:** http://opensource.org/licenses/MIT  
@@ -150,6 +150,11 @@ For reasons of data protection, it is not possible to see the followers of other
 
 ## Changelog ##
 
+### 3.3.1 ###
+
+* Fixed: PHP Warnings
+* Fixed: PHPCS issues
+
 ### 3.3.0 ###
 
 * Added: Content warning support
diff --git a/activitypub.php b/activitypub.php
index f191f9f6b..d2381957e 100644
--- a/activitypub.php
+++ b/activitypub.php
@@ -3,7 +3,7 @@
  * Plugin Name: ActivityPub
  * Plugin URI: https://github.com/pfefferle/wordpress-activitypub/
  * Description: The ActivityPub protocol is a decentralized social networking protocol based upon the ActivityStreams 2.0 data format.
- * Version: 3.3.0
+ * Version: 3.3.1
  * Author: Matthias Pfefferle & Automattic
  * Author URI: https://automattic.com/
  * License: MIT
@@ -23,7 +23,7 @@
 require_once __DIR__ . '/includes/compat.php';
 require_once __DIR__ . '/includes/functions.php';
 
-\define( 'ACTIVITYPUB_PLUGIN_VERSION', '3.3.0' );
+\define( 'ACTIVITYPUB_PLUGIN_VERSION', '3.3.1' );
 
 /**
  * Initialize the plugin constants.
diff --git a/readme.txt b/readme.txt
index 5949de8cd..52bc40e9e 100644
--- a/readme.txt
+++ b/readme.txt
@@ -3,7 +3,7 @@ Contributors: automattic, pfefferle, mediaformat, mattwiebe, akirk, jeherve, nur
 Tags: OStatus, fediverse, activitypub, activitystream
 Requires at least: 5.5
 Tested up to: 6.6
-Stable tag: 3.3.0
+Stable tag: 3.3.1
 Requires PHP: 7.0
 License: MIT
 License URI: http://opensource.org/licenses/MIT
@@ -148,6 +148,11 @@ For reasons of data protection, it is not possible to see the followers of other
 
 == Changelog ==
 
+= 3.3.1 =
+
+* Fixed: PHP Warnings
+* Fixed: PHPCS issues
+
 = 3.3.0 =
 
 * Added: Content warning support