Is this resolved?
If it is not resolved, can you please share all zip logs?
This issue is not yet resolved, although the support case has been escalated to the engineers, so I have my fingers crossed for good news soon.
The installer makes use of a file call ARSystemInstalledConfiguration.xml file located under the ARSystem directory. Before you think of running the upgrade or install. You would like to check with that file and search with keyword PLUGIN-PORT. If that is present, then you know why the installer is picking up. You need to correct it there and then run the upgrade to ensure it actually picks up the port number.