Thanks for asking, you can actually always install a new version of the Squeezebox Server if its compatible with our Raspbian (stretch with 4.19 kernel at the moment) and in the .deb format.
The 7.9.2 is still in the beta folder at the slimdevices ressources and I cannot find an official release thread in the forums either. So I think it’s still not officially out. However, you can try installing the new version by pasting the link in our installer in the web interface. Make sure you give the installer a lot of time (ca 15 minutes) to ensure it installs correctly. I check and this link worked for me with the newest version of Max2Play (2.48 image): Link