diff --git a/ansible_mitogen/target.py b/ansible_mitogen/target.py
index 6e128af4..199f3a14 100644
--- a/ansible_mitogen/target.py
+++ b/ansible_mitogen/target.py
@@ -40,7 +40,6 @@ import errno
 import grp
 import json
 import logging
-import operator
 import os
 import pty
 import pwd
@@ -66,8 +65,6 @@ if not sys.modules.get(str('__main__')):
 
 import ansible.module_utils.json_utils
 
-from ansible.module_utils.six.moves import reduce
-
 import ansible_mitogen.runner
 
 
@@ -718,7 +715,9 @@ def apply_mode_spec(spec, mode):
             mask = CHMOD_MASKS[ch]
             bits = CHMOD_BITS[ch]
             cur_perm_bits = mode & mask
-            new_perm_bits = reduce(operator.or_, (bits[p] for p in perms), 0)
+            new_perm_bits = 0
+            for perm in perms:
+                new_perm_bits |= bits[perm]
             mode &= ~mask
             if op == '=':
                 mode |= new_perm_bits
diff --git a/docs/ansible_detailed.rst b/docs/ansible_detailed.rst
index e692c43a..ff5f9dcb 100644
--- a/docs/ansible_detailed.rst
+++ b/docs/ansible_detailed.rst
@@ -145,6 +145,8 @@ Noteworthy Differences
   +-----------------+ 3.11 - 3.14     |
   | 12              |                 |
   +-----------------+-----------------+
+  | 13              | 3.12 - 3.14     |
+  +-----------------+-----------------+
 
   Verify your installation is running one of these versions by checking
   ``ansible --version`` output.
diff --git a/docs/changelog.rst b/docs/changelog.rst
index 4ffab849..7b02c56e 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -21,6 +21,11 @@ To avail of fixes in an unreleased version, please download a ZIP file
 In progress (unreleased)
 ------------------------
 
+* :gh:issue:`1237` :mod:`mitogen`: Re-declare Python 2.4 compatibility
+* :gh:issue:`1385` :mod:`ansible_mitogen`: Remove a use of
+  ``ansible.module_utils.six``
+* :gh:issue:`1354` docs: Document Ansible 13 (ansible-core 2.20) support
+
 
 v0.3.35 (2025-12-01)
 --------------------
diff --git a/docs/index.rst b/docs/index.rst
index 32083db0..220a7fff 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -332,12 +332,16 @@ a large fleet of machines, or to alert the parent of unexpected state changes.
 Compatibility
 #############
 
-Mitogen is compatible with **Python 2.4** released November 2004, making it
+``mitogen.*`` is compatible with Python 2.4 - 2.7 and 3.6 onward; making it
 suitable for managing a fleet of potentially ancient corporate hardware, such
 as Red Hat Enterprise Linux 5, released in 2007.
 
-Every combination of Python 3.x/2.x parent and child should be possible,
-however at present only Python 2.4, 2.6, 2.7 and 3.6 are tested automatically.
+Every combination of Python 3.x/2.x parent and child should be possible.
+Automated testing cannot cover every combination, automated testing tries to
+cover the extemities (e.g. Python 3.14 parent -> Python 2.4 child).
+
+``ansible_mitogen.*`` is compatible with Python 2.7 and 3.6 onward; making it
+suitable for Ansible 2.10 onward.
 
 
 Zero Dependencies
diff --git a/setup.py b/setup.py
index ad60847e..047b7e86 100644
--- a/setup.py
+++ b/setup.py
@@ -82,7 +82,7 @@ setup(
     license = 'BSD-3-Clause',
     url = 'https://github.com/mitogen-hq/mitogen/',
     packages = find_packages(exclude=['tests', 'examples']),
-    python_requires='>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*',
+    python_requires='>=2.4, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*',
     zip_safe = False,
     classifiers = [
         'Environment :: Console',
@@ -91,6 +91,9 @@ setup(
         'Operating System :: MacOS :: MacOS X',
         'Operating System :: POSIX',
         'Programming Language :: Python',
+        'Programming Language :: Python :: 2.4',
+        'Programming Language :: Python :: 2.5',
+        'Programming Language :: Python :: 2.6',
         'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.6',
diff --git a/tests/image_prep/hosts.ini b/tests/image_prep/hosts.ini
index 254643a7..0c57e914 100644
--- a/tests/image_prep/hosts.ini
+++ b/tests/image_prep/hosts.ini
@@ -43,6 +43,7 @@ centos7
 centos8
 debian9
 debian10
+ubuntu1604
 ubuntu1804
 
 [ansible_11]
diff --git a/tox.ini b/tox.ini
index 28c97496..3ef977ac 100644
--- a/tox.ini
+++ b/tox.ini
@@ -63,7 +63,7 @@ envlist =
     py{27,36}-m_ans-ans{2.10,3,4}
     py{311}-m_ans-ans{2.10,3-5}
     py{313}-m_ans-ans{6-9}
-    py{314}-m_ans-ans{10-12}
+    py{314}-m_ans-ans{10-13}
     py{27,36,314}-m_mtg
     report,