The 2 flights before that were not plagued by the incorrect AoA but some other problem, at least that's how i read the various news reports.
I don’t share your memory. I have not seen any reports from the 2 flights before.
I’m sure the investigators are looking at those flights, but so far, no leaks to my knowledge.
There is a big question of course, due to the knowledge that an AoA vane was swapped out during the transit between flights 2 and 3 (if we can number them 1-4, 4 being the accident flight).
That AoA vane was swapped out for a reason, but we don’t exactly know the reason. It is reasonable to assume it was swapped out as a troubleshooting attempt from a pilot report of an air data problem from the incoming flight, Now this is where it gets interesting, and this is where we need information that we simply don’t have.
So, I try to keep my comments relevant to Professional Pilots.
Technical discussions can be carried on in the Tech Log forum, and there is one regarding MCAS.