According to Trevor Packer, the AP awards are going away, although he did not specify timing.
My understanding is that for all intents and purposes, the revised APWH is simply a revision, so a retake would only count once.
Comp Sci AB was an extension of Comp Sci A.much like Calc AB and Calc BC, so probably counted twice. I’m never heard of anyone taking AP Physics 1/2 after AP Physics B, but since 1/2 were new exams, my guess is taking them all counted as 3 exams.