Updating Ubuntu from a dev version that is no-longer supported

Whatever you do, make a backup copy of /etc/apt/sources.list first!

Two alternatives:

1. Simply change the name of the version in /etc/apt/sources.list
   • e.g from impish to jammy
2. Run a script, after modifying it to exactly tee mirror you’re using:

sed -i -e 's/gb.archive.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list