Just a data point since the current 2x/$ on Amex GCs is a phenomenal deal: I purchased my GCs on 12/9, had them approved 12/10, and the points showed as pending on Flystore early today (12/11). FWIW BeFrugal usually posts within 5 hours of purchase (even before approval, although they get clawed back if you are declined).

Slight weirdness, though -- the purchase was $2000 (+3.95), and it's showing up as 3981 pending points. I'm not inclined to argue that though