I just upgraded to wily werewolf beta. It seems that by default, my sources.list (here's the file: http://pastebin.com/FE0NyzNk) contains something wrong. I get 404 error when doing update when connecting to some of the sources. For some reason many of them seem to be located at old-releases.ubuntu.com.
I generated a new source.list file from this website, http://repogen.simplylinux.ch/, and now everything seems to work. However, if I touch settings in software & updates tool, it again adds crap to the file.
Is this a bug or do I have some old broken sources.list stored somewhere and the tool is trying to get the default entries from there or what?
EDIT: output of
lsb_release -a is:
No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu Wily Werewolf (development branch) Release: 15.10 Codename: wily