CheckMK Appliance upgrade: Syntax error in step 42

CMK version: 2.4.20
OS version: Appliance 1.7.14

Error message:

Reset deprecations scheduling" failed
-| Traceback (most recent call last):
-|   File "/omd/sites/NanoBiophotonics/lib/python3/cmk/update_config/main.py", line 271, in update_config
-|     action(logger)
-|   File "/omd/sites/NanoBiophotonics/lib/python3/cmk/update_config/plugins/actions/deprecations.py", line 18, in __call__
-|     job_scheduler.reset_scheduling("execute_deprecation_tests_and_notify_users")
-|   File "/omd/sites/NanoBiophotonics/lib/python3/cmk/gui/job_scheduler/_scheduler.py", line 102, in reset_scheduling
-|     for ident, datetime in _load_last_job_runs().items()
-|                            ^^^^^^^^^^^^^^^^^^^^^
-|   File "/omd/sites/NanoBiophotonics/lib/python3/cmk/gui/job_scheduler/_scheduler.py", line 83, in _load_last_job_runs
-|     for ident, ts in store.load_object_from_file(
-|                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-|   File "/omd/sites/NanoBiophotonics/lib/python3.12/site-packages/cmk/ccc/store/__init__.py", line 210, in load_object_from_file
-|     return ObjectStore(Path(path), serializer=DimSerializer()).read_obj(default=default)
-|            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-|   File "/omd/sites/NanoBiophotonics/lib/python3.12/site-packages/cmk/ccc/store/_file.py", line 195, in read_obj
-|     return self._serializer.deserialize(raw) if raw else default
-|            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-|   File "/omd/sites/NanoBiophotonics/lib/python3.12/site-packages/cmk/ccc/store/_file.py", line 74, in deserialize
-|     return literal_eval(raw.decode("utf-8"))
-|            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-|   File "/omd/sites/NanoBiophotonics/lib/python3.12/ast.py", line 66, in literal_eval
-|     node_or_string = parse(node_or_string.lstrip(" \t"), mode='eval')
-|                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-|   File "/omd/sites/NanoBiophotonics/lib/python3.12/ast.py", line 52, in parse
-|     return compile(source, filename, mode, flags,
-|            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-| SyntaxError: source code string cannot contain null bytes


The update of the site itself works completely fine, no problems at the end. But this syntax error is a bit confusing