Updating Calibre

[Moltke]

The Calibre e-book reader from supported repositories of LL 3.8 is stuck on version 2.55. Is there a reliable way of getting a newer 32-bit version? I really enjoy Calibre on my little Acer Aspire One running LinuxLite 3.8 (as opposed to a bigger laptop, not fitting into a lap). Should I run the instructions for Linux on the Calibre web site or should I add another (unknown) repository to the updates? I am not afraid of running command lines, but the numerous dependencies are off-putting. And I expect the restore points shoud guard me against disasters. NOTE: I use Calibre for open EPUB books only.

I think the safest option is to try calibre's site instructions, just don't install latest 5.10, that one won't work. If you can, use a VM; install Linux Lite in a VM and try there. Newer Calibre versions require python >= 3.7 and Xenial doesn't have that, I think.  You could also give a try to this https://ubuntu.pkgs.org/18.04/ubuntu-uni...l.deb.html, again, it does require newer python so...try in a VM for safety.
If I may ask, do you need something specific from a new Calibre version? Because if you don't and 2.55 is working fine, then maybe the best is to leave it as it is. You could upgrade your system too.
Hope this helps!