Tor Browser Updater by Whonix developers correctly detected this.
The signature creation date is outdated indeed.
Bug reported upstream at The Tor Project just now:
- Do nothing.
- Check what upstream replies.
- Wait for a new release where this is fixed or if upstream re-signs the release with a proper gpg signature creation date.
Not a Whonix issue. This is reproducible without Whonix being involved. Unspecific to Whonix.