Hmm I might be in the same boat as you.My Teric just got back from service for a broken AI antenna. According to them, almost all of the components were replaced along the way and it was on its way back to me in like 3 days. Very impressed with the service. Mine was a couple years old, but only had about 40 dives on it. It only died when I updated to V. 21, I think. Weird.
My AI antenna's broken too and I did a V. 22 upgrade - unfortunately I didn't check whether AI was working prior to the upgrade, so I don't know if it's a coincidence or firmware-induced.
It was last working in Nov 2021, then I did some diving in Feb 2022 with AI turned off, and in Mar 2022 I upgraded to V. 22 and found out later that AI stopped working.