This problem is fixed with the edgy upgrader. It will always ensure that the main distro repostiory is avialable.
** Changed in: update-manager (Ubuntu) Status: Needs Info => Fix Released -- [dist-upgrader] trying to upgrade to dapper https://launchpad.net/bugs/40715 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs