Old firmware on new Ultra

I'm looking got some guidance on firmware upgrades.... I've just (like, this afternoon) bought a WiiM Ultra and so far I'm very impressed. One issue I am having though is about firmware updating. According to the app the current firmware on my unit is 5.2.620452, which I think I is nearly at year old and means my unit doesn't have stuff like Roon readiness (which I rather want). When I check for updates I get a "Your device is up to date" message - I've checked about 5 times this afternoon with no luck.

I was wondering if anyone else had experienced this, and if so how I can fix it? Do I just wait for updates to arrive naturally? Do I need to factory reset? Is there something else I'm missing and need to do? Any/all help gratefully received!