As your system was bootable I'm refiling this bug against ubuntu- release-upgrader which is more appropriate for the problems that you've experienced.
** Package changed: grub-installer (Ubuntu) => ubuntu-release-upgrader (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1583664 Title: My upgrade from 14.04 was very buggy, so re-install necessary. It crashed. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1583664/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
