I am just an electronics engineer (non-aero) _and_ I may well have missed some important information from this discussion.
But earlier, I think it was mentioned that either one or the other of two possible sources of AoA information is selected "automatically" and remains throughout the flight, then switch to the other one for the next flight. Is this more or less correct? What is the rationale behind this? To me it appears as "we did not quite know what to do with two AoA sensors here". Presumably this also went through some review by the FAA ... who were happy with the explanation?