After an update to UTM 9.4 SR I could kiss my mesh goodbye. I experienced it first with a SG135 and 2 AP50's with a mesh on 5GHz, After the update the band used for mesh seems disabled on the AP, when the AP is a Mesh Access Point. You can check this in the UTM WebConsole, with a tool like Wifi Explorer, and the blue light going off for the corresponding band on the AP: A Root Access Point still has both 2.4 and 5 GHz.
After creating a new mesh on 2.4 GHz, the MAP switches off its 2.4GHz capability.
Today I tried to reproduce it on a SG210 and 2 different AP50's. As long as it was running the old 9.355 firmware the mesh just worked fine, on 2.4 and 5 Ghz. After installing SR 9.4, the same behaviour can be observed (no 2.4 or 5GHz activity, depending on what is used for mesh).
This deprived me of a wired connection in my office at home.
My question: is anyone else running a mesh, and has anyone else experienced this behaviour?