Comment 8 for bug 1907920

Mirrors are free to drop a release anytime AFTER the release reaches EOL.

The month is known (ie. 19.10 meant the 2019-October release, so it'll be 9 months after release date), though the EOL may not occur 9 months to the day, but between that date & end-of-the-month.

19.10 reached EOL, and was announced - https://fridge.ubuntu.com/2020/07/17/ubuntu-19-10-eoan-ermine-end-of-life-reached-on-july-17-2020/

meaning mirrors can drop the release the following day if they like, or any date after that. The main archive will also occur, as listed AFTER the release reaches EOL (ie. moved from archive.ubuntu.com to old-releases.ubuntu.com). There is no set date, except it occurs AFTER eol.

19.10 reached EOL long ago, the release name (19.10) makes the EOL easy to calculate, making it easy to schedule & plan when you need to release-upgrade (6-9 months after 2019-October), so your wasted time I'd see more as a management issue (lack of planning).

3rd party packages can use versioning tricks (higher values put on packages than what is actually enclosed) to ensure they install & replace official repositories, but this creates problems come release-upgrade time; thus the removal step (ppa-purge etc). (I'm assuming the camera package is 3rd party, but you gave no specifics)

Either way, unless problems exist in a currently supported upgrade path (eg. 20.04 release-upgrading to 20.10), eoan being EOL shouldn't have had any users for months now.

Note: this is my opinion (based on my Ubuntu knowledge).

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