I’ve been cruising along in a Argon One M.2 running Home Assistant OS since dev5.6 pretty happily, now comfortably running 5.9.
This was a clean install after running Supervised in Raspberry Pi OS for the last year (I had a lot of crud to wanted to clean out, restoring a snapshot should work fine if you’re not after a clean start).
I wrote up how I got it working here if you want to have a look through (it’s also kind of a review of the case at the start, so it’s a bit of a read).
I’m going to update it to just be going to 5.9 directly today, as well as redo the fan control portion as an addon has just been written to contain all that completely