qBittorrent official forums

can't upgrade 4.3.1. on Ubuntu 18.04.6 LTS - says "latest version is already installed"

what am i missing?

thanks

The support for Ubuntu 18.04 si dropped so neither the Ubuntu repo nor the PPA will be updated.
https://www.qbittorrent.org/news.php (see March 24th news).

I think it's the same for 20.04 but here you have an appimage that may work (see the same page)
LINUX: An AppImage is now offered. It uses the latest versions of Qt6, libtorrent, boost, openssl. It is created on Ubuntu 20.04 and it should work on any other similarly aged distro. It isn't well tested. Also Ubuntu 20.04 is dropped from the PPAs because it doesn't have the minimum required Qt5 version (5.15.2). The AppImage should cover any users left on that version.

Well, after all it is strange that qBittorrent version 4.4.1 isn't available on any LTS version.
And not available on Ubuntu 22.04, that have all the needed software packages.

Or have I misunderstood something?

Ubuntu 20.04 is not supported anymore (Qt is too old in it), it's recommended to use the AppImage there.
And Ubuntu 22.04 is not out yet, it's in a pre-release state.

For daily use, I'd highly recommend using just the latest Ubuntu/Kubuntu/Xubuntu version available.
Ie.: Not the LTS one, but whatever is "current". You can seamlessly upgrade from LTS to the current version and so on.
(Current version is 21.10)

If you only need the "nox" version (webUI), please check out the qbittorrent-nox-static project: https://github.com/userdocs/qbittorrent-nox-static
This project is not affiliated with qBittorrent, but it is used by many.