So you have the latest SPAR software for the device. Is IPv6 disabled or enabled on the device?
Airprint has been working on this printer in this environment flawlessly for years. However now it's not happy.
I can see that when the printer boots up airprint also starts up and publishes information, however after 20 seconds it stops broadcasting. I suspect something is crashing in the printer.
I've reset the printer to factory defaults, yet I'm still not able to get airprint to remain running.
Current Version: 65.69.51