Final update/data point.

I previously had the USAirways branded Barclay card that was converted to the AAdvantage Red card from Barclays. Actually I *have* this card. I applied for the "new" AAdvantage Red card and got the pending status. 8 days later (at like 8:30 a.m. on Sat or Sunday) I got a phone call from Barclays and they wanted to move some credit limit around (I also previously had the Barclay World Elite whatever card and had closed that after moving the entire CL to the converted Red card).

AF was posted on account on 3/31/17.
I charged some Amazon gift card to the card on 4/5/17.
Paid full balance on 4/7/17.
First statement closing was 4/21/17.

Miles posted (like previously poster said) 2 days later on 4/23/17. However, it didn't show up on Barclays website as miles earned. But I logged into aa.com and there were the 40k miles (well plus whatever I charged).

Good luck, all!