Ubuntu
ubuntu-release-upgrader package

  1. Bionic (18.04)
  2. Bug #1898026
  3. Comment #6

Comment 6 for bug 1898026

Revision history for this message
Brian Murray (brian-murray) wrote : Re: upgrade to 20.04 is quite invasive

Thinking about this more I suspect what happened was that the release upgrade process (running 'sudo do-release-upgrade -m desktop') was interrupted at a point after it had modified your /etc/apt/sources.list file to focal. Then when 'dist-upgrade' was run because your sources.list file now containted focal all the packages from focal were installed. The release upgrade process should do a better job of restoring your sources.list file in the event that it is interrupted (Ctrl-C).

Also for what its worth do-release-upgrade has a '-c' switch which specifically only checks if a new distribution release is available.