This does not seem to be related to the changes introduced in the latest ubuntu-release-upgrader packages in -proposed. From the logs it seems that there was an issue installing ubuntu-minimal - I predict it is caused by either a corrupted or modified sources.list on the upgraded system.
** Tags added: bot-stop-nagging -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1851902 Title: 16.04 LS to 18.04update crash To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1851902/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
