diff --git a/doc/api/prev_api_changes/api_changes_3.1.0.rst b/doc/api/prev_api_changes/api_changes_3.1.0.rst
index 7088b4b010f5..9206495ed683 100644
--- a/doc/api/prev_api_changes/api_changes_3.1.0.rst
+++ b/doc/api/prev_api_changes/api_changes_3.1.0.rst
@@ -17,14 +17,6 @@ regardless of whether `matplotlib.pyplot` has been imported. If the user
 tries to switch from an already-started interactive backend to a different
 interactive backend, an `ImportError` will be raised.
 
-mplot3d auto-registration
-~~~~~~~~~~~~~~~~~~~~~~~~~
-
-`mpl_toolkits.mplot3d` is always registered by default now. It is no
-longer necessary to import mplot3d to create 3d axes with ::
-
-  ax = fig.add_subplot(111, projection="3d")
-
 Invalid points in PathCollections
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 PathCollections created with `~.Axes.scatter` now keep track of invalid points.
diff --git a/doc/api/prev_api_changes/api_changes_3.2.0/behavior.rst b/doc/api/prev_api_changes/api_changes_3.2.0/behavior.rst
index e99f3e2c021e..0d8933fb363b 100644
--- a/doc/api/prev_api_changes/api_changes_3.2.0/behavior.rst
+++ b/doc/api/prev_api_changes/api_changes_3.2.0/behavior.rst
@@ -299,3 +299,11 @@ package, and Axes methods that take a ``norm`` parameter.
 
 If extra kwargs are passed to `.LogScale`, `TypeError` will now be
 raised instead of `ValueError`.
+
+mplot3d auto-registration
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+`mpl_toolkits.mplot3d` is always registered by default now. It is no
+longer necessary to import mplot3d to create 3d axes with ::
+
+  ax = fig.add_subplot(111, projection="3d")