No worries, I’m also not that much of a fast replyer.
Have you disabled auto start in the DHCP profile?
I probably could have been a bit clearer what I mean too: Those profiles with DHCP enabled in network manager should have a ‘Connect automatically’ toggle, maybe try just turning them off instead of deleting them, and make sure they’re turned on for the static IP profile.
I also haven’t used Xubuntu in a while, and this is mostly for Debian KDE and Ubuntu, so I’m hoping it’s the same.