macOS. Issues with releases built with --archive-format=zip
macOS, Plugin: SCP
command example:
$ pyupdater build --app-version=2.0.1 --archive-format=zip -wyD mac.spec
tar.gz-release successfully updates to the next tar.gz-release
zip-relase doesn't "see" next zip-release
zip-relase doesn't "see" next tar.gz-release
tar.gz-release crashes when trying to update to the next zip-release
I found that the content of the app packages is different between zip and tar.gz.
There are some aliases to directories in Resources in tar.gz-releases.
In zip-releases these are empty directories instead of aliases.
Zip-release can't find local certificate file while trying to make update_check.

It seams that the problem is with shutil.make_archive. It changes symlinks to empty folders when making zip file. (macOS, Python 3.8.1)
Found open ticket https://bugs.python.org/issue37601
Thanks for the report & great find!
Looks like we'll need to do it the long way :)