diff --git a/scripts/snap_pac.py b/scripts/snap_pac.py
index 080c513..b5b235b 100755
--- a/scripts/snap_pac.py
+++ b/scripts/snap_pac.py
@@ -150,7 +150,8 @@ class Prefile:
             try:
                 pre_number = self.file.read_text()
             except FileNotFoundError:
-                raise FileNotFoundError(f"prefile {self.file} not found. Ensure you have run the pre snapshot first.")
+                pre_number = None
+                logging.warning(f"prefile {self.file} not found. Ensure you have run the pre snapshot first.")
             else:
                 self.file.unlink()
         return pre_number