Ubuntu 22.04.1: опция apt-offline get --bundle не работает

Опция --bundle file.zip не работает. Что я делаю не так?

Убунту 22.04.1

      ~ $ apt-offline set --update --upgrade offline.sig
~ $ apt-offline get offline.sig --bundle offline.zip

Fetching APT Data

Downloading http://security.ubuntu.com/ubuntu/dists/jammy-security/Release.gpg                                                             
http://security.ubuntu.com/ubuntu/dists/jammy-security/Release.gpg done                                                             
Exception in thread Thread-1 (run):#############] 100.0% of 0 KiB
Traceback (most recent call last):
  File "/usr/lib/python3.10/threading.py", line 1016, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.10/threading.py", line 953, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib/python3/dist-packages/apt_offline_core/AptOfflineLib.py", line 691, in run
    if threading.currentThread().guiTerminateSignal:
  File "/usr/lib/python3.10/threading.py", line 1449, in currentThread
    warnings.warn('currentThread() is deprecated, use current_thread() instead',
DeprecationWarning: currentThread() is deprecated, use current_thread() instead

Downloaded data to offline.zip

Как видите, --bundle offline.zip на самом деле не загружает никакой другой подписи PGP.

Однако опция -d DIRECTORY работает нормально.