"Unsupported OS" error when upgrading to 5.1

Tried the upgrade to 5.1, got the error that I have an unsupported OS. I am running Ubuntu 19.10 and the previous installs/upgrades for Pihole have been flawless. A bit surprised by this now. I can set the flag to skip the OS check but then does that set some config value that will create issues down the line?

How does Pihole determine that Ubuntu 19.10 is unsupported?

I'm not sure if 19 is intentionally left out by the @Developers. Currently it compares your distribution name and the version number with the supportedos.txt

Thanks very much for that pointer. It is indeed strange that 19 is left out. Will wait to hear details from @Developers on the reasoning before taking action.

Not an official statement, but I'd guess that dev support is trying to focus on the LTS versions.

Just to clarify: Ubuntu 19 wasn't supported before, it's just that 5.1 now checks for supported OS versions.

Unsupported OS doesn't mean Pi-hole won't run on it, but you do so at your own convenience. You should also be prepared to resolve issues when updating to a new version yourself, as the Pi-hole team will dedicate resources to test supported OS only.

That doesn't mean you're on your own - the Pi-hole community is a pretty helpful one, and you'll find that users as well as developers will offer as much advice as they can, regardless of the OS you're running.

They test Pi-hole on all platforms they support with virtual machines (there was a post about this somewhere). The quoted list already lists 11 operating systems / versions. Adding 17 and 19 creates additional work for them and maybe such systems cannot even be updated any longer.

Here's the solution in case someone else runs into this:
sudo PIHOLE_SKIP_OS_CHECK=true pihole -up

Actually it is stored as a TXT record on versions.pi-hole.net

[adam@ADAM-PC ~]# dig +short -t txt versions.pi-hole.net
"Raspbian=9,10 Ubuntu=16,18,20 Debian=9,10 Fedora=31,32 CentOS=7,8"