diff --git a/AUTHOR b/AUTHOR
index d2bcd8b4e6ba1649aab5ee08adcebf6c4d9f1767..8265ee1e9681ee905406ca55ff4a2c3b689ad4ad 100644
--- a/AUTHOR
+++ b/AUTHOR
@@ -4,4 +4,5 @@ Matthew Webster <matthew.webster@ndcn.ox.ac.uk>
 Sean Fitzgibbon <sean.fitzgibbon@ndcn.ox.ac.uk>
 Martin Craig <martin.craig@eng.ox.ac.uk>
 Taylor Hanayik <taylor.hanayik@ndcn.ox.ac.uk>
-Evan Edmond <evan.edmond@ndcn.ox.ac.uk>
\ No newline at end of file
+Evan Edmond <evan.edmond@ndcn.ox.ac.uk>
+Christoph Arthofer <christoph.arthofer@ndcn.oxc.ac.uk>
\ No newline at end of file
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 4194febbc5d573f6fe919ebe63057dfb9656a9e8..600ac1d8d7a7460a59da51a55eea5a4e213f85c5 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -2,6 +2,17 @@ This document contains the ``fslpy`` release history in reverse chronological
 order.
 
 
+3.6.4 (Tuesday 3rd August 2021)
+-------------------------------
+
+
+Added
+^^^^^
+
+
+* New :meth:`.fslmaths.kernel` and :meth:`.fslmaths.fmeanu` options on the
+  :class:`.fslmaths` wrapper (!304).
+
 
 3.6.3 (Wednesday 28th July 2021)
 --------------------------------