LTS means long term support. in the sense that the OS will continue to receive updates and security patches for a long time, for Ubuntu 16.04, this means Canonical will stop supporting this OS at around Apr 2021.
So the OS itself has long term support, but it seems the makers of JRiver only releases deb for the latest Ubuntu... It's like LTS means nothing to them.
Why do I stick on 16.04 still? Frankly, because it sounds better. I don't really understand why, probably because we have spent years tweaking the sound. Changing the OS can alter that, e.g. I can never get 18.04 to sound like 16.04, and why I'm still on 16.04... But JRiver and HQPlayer have moved on. Do they just built their software on the latest platform, because it sounds better, or because, while the OS is newer?
Well, I'll never know. But moving forward, Snakeoil will be moving to 20.04 (as 16.04 support will end). When that happens, we restart the cycle to find the kernel that sounds best. Will also think of a way to make Snakeoil less depedent on the underlying OS... i.e. you guys can use any debian based system you want, and Snakeoil will work.. and so we can expand our reach, and thereby also increases the likelihood of finding a good sound combination.
So from the likes of it, JRiver Media27 will only work on Ubuntu 20.04... I hope to rush this out in the Dec holidays.