According to Gitlab Upgrade recomendations, you can’t skip a major version. So to go from 10.6.4-ee.0 to 12.10.3-ce.0, a few intermediate steps are neccesary.

My Ubuntu 20.04 laptop did not show an entry for enp0s25, only for wireless connections. This way, I could not connect to a VPN unless I was using the wireless connection that NetworkManager actually saw.