Ah, right. do-release-upgrade loads the meta-release file information from http://changelogs.ubuntu.com/meta-release with some modifications for the -d (-development) and -p (-proposed) switches. However, meta-release-proposed doesn't contain information about Vivid nor does it point to the vivid-proposed version of the release upgrader. I'll fix that now.
Ah, right. do-release-upgrade loads the meta-release file information from http:// changelogs. ubuntu. com/meta- release with some modifications for the -d (-development) and -p (-proposed) switches. However, meta-release- proposed doesn't contain information about Vivid nor does it point to the vivid-proposed version of the release upgrader. I'll fix that now.