diff --git a/CHANGELOG.md b/CHANGELOG.md
index 77fe29b8a47d3d2d560e320ddfe79261d7c9ee17..9d40cc7865b733e1fde3e95323cb8dc31588bdfe 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,11 @@
+Changes in Release 3.1.1
+=================================================================================
+
+* `run_af2` Python package:
+  * Adapt to new AF2 versioning scheme
+  * Fallback for picking up the Singularity image automatically
+
+
 Changes in Release 3.1.0
 =================================================================================
 
diff --git a/run_af2/src/run_af2/run_singularity.py b/run_af2/src/run_af2/run_singularity.py
index 1fe4bd23094ebdde35020181da4f31c3321c5583..e55a9b3022a3f70d1306400b0b789415955b8c6d 100644
--- a/run_af2/src/run_af2/run_singularity.py
+++ b/run_af2/src/run_af2/run_singularity.py
@@ -179,7 +179,9 @@ def _assemble_singularity_call(  # pylint: disable=too-many-arguments
 def _determine_af2_image(af2_image_dir):
     """Select an image from a given directory. File name of the images need to
     be of form alphafold-<YYYY-MM-DD>.sif. The path to the latest image will be
-    returned, determined by the '<YYYY-MM-DD>' component of the file name."""
+    returned, determined by the '<YYYY-MM-DD>' component of the file name. If
+    the file name is of different form, an arbitrary file ending with '.sif'
+    will be used."""
     lst_mtch = "0000-00-00"
     af2_path = ""
     af2_files = os.listdir(af2_image_dir)
@@ -194,6 +196,8 @@ def _determine_af2_image(af2_image_dir):
             if mtch.group(1) > lst_mtch:
                 af2_path = af2_file
                 lst_mtch = mtch.group(1)
+        elif af2_file.endswith(".sif"):
+            af2_path = af2_file
     af2_path = os.path.join(af2_image_dir, af2_path)
 
     return af2_path