So, if you find that your kinetic install is end of life, follow these steps to upgrade to 23.04.
Open a terminal and type in sudo nano /etc/apt/sources.list and change all ‘archive.ubuntu.com’ (Or a mirror that you’re using) entries to old-releases.ubuntu.com
Press CTRL+X to save your changes and confirm by pressing yes.
Press enter to exit and type in: sudo apt update && sudo apt upgrade then reboot.
After rebooting, open a terminal and type in sudo do-release-upgrade. Follow the prompts and reboot.
And, congratulations! You have sucessfully upgraded to lubuntu 23.04!
As is Ubuntu’s practice (I’m on the Ubuntu News team too, thus why I use that timing), the aim is to put those warning notices ~six weeks before EOL occurs, so users have time to plan their release-upgrade, before its made harder after that date (ie. an EOLUpgrade which is what @BasilCat is writing about).
Also FYI: If you’re using a country mirror; the country code will also need to be removed, eg. being an aussie if I was using my country’s mirror being au.archive.ubuntu.com the au. would need to be removed as well as no country mirrors exist for old-releases.ubuntu.com.
Ubuntu 16.10’s intended release-upgrade path was to 17.04 or the next release, with the upgrade path disappearing when 17.04 reached EOL.
LTS releases have two upgrade paths:
to the next release like your 16.10 non-LTS had (to 17.04), or
to the next LTS release (an unsupported path for non-LTS unless from prior release)
If it was me, I’d backup all data on your system, and either
clean install & restore the data you need
unclean install a supported release of Lubuntu over your existing install…
The clean install I’d expect to have best results; and do note I’d only restore the data you need given how old your system is, rather than everything - but that’s me.
The unclean install I’d use is documented here and listed as “Install using existing partition” being something we test in our Quality Assurance testing, however do NOTE as 16.10 is so old & past EOL, I’d perform homework where data matters to you before I actually did it prior to doing it, given you’re talking about doing a unclean install with a very different system; esp. if your data matters to you.
Also FYI: Returning to 16.04 may not help you either, as it’s path to 18.04 really ended when EOSS was reached and that upgrade path closed anyway (though it may still work; but problems would now be expected given it’s no longer a supported upgrade due to EOSS).
FYI: I really like the unclean install method I mention, and often use it as faster than normal release-upgrades, however it’s results will vary depending on what 3rd party packages you have installed, as QA of it only include Ubuntu repository packages.
If I remember correctly, the update from LXDE to LXQt was never supported. So you can save your time and freshly install a currently supported version with LXQt.
The Lubuntu team never did support it, so you’re correct. The supported path would only get you to Lubuntu 18.04 LTS which is EOL.
Documentation was written to aid in the process of 18.04 (LXDE) to 18.10 (LXQt), however it never appeared in published form in our manual, and was never supported.
I personally upgraded many old Lubuntu (LXDE) systems to LXQt; my primary system took me three weeks of work before it was reliable, a process I’d not want to repeat… but this was a system I’ve heavily modified & had loads of additional packages installed. Other systems that are less critical to me (and had fewer changes) I release-upgraded without issue. How difficult it was varied depending on what people had done to their systems, thus it was never supported.
That just stresses the re-install options.
FYI: I may have done more than eight Lubuntu LXDE to LXQt conversions, but it was so long ago now, I’d not advise anyone as it was too long ago, and the documentation that existed back then I don’t believe exists today.
Ubuntu Desktop including flavors like Lubuntu, allow you to re-install a Desktop system non-destructively not losing a single data file (anything stored in /home won’t be touched) or setting (as long as it’s too stored in /home, and not a system wide setting in a system directory).
A separate /home is preferred by most GNU/Linux users because not all GNU/Linux distributions can do this, but Ubuntu (including Lubuntu) can easily. You just select your existing partitions & ensure you don’t haveformat checked.