I got mine during the 100XP promo earlier this year.
Everything went fast and smoothly for the most part.
Approval within a few days of the application (virtual card issued at the same time).
100XP posted within about a week of the approval, without having used the card at all.
Received the physical card about a week later.
Accelerator miles posted at the same time as regular FB miles from flying.
Spend miles posted exactly a month after transaction (used it only once though so may be a one-off).

The only minor hiccup I had was with my additional cardholder getting the bonus 100XP. It wasn't posted when I got mine. Had to call Brim to update her FB number because it wasn't saved properly in the system (had to prefix her number with 2 extra 0s in the application form because the form was requiring wrong length of FB number for the additional cardholder). She got her bonus right the next day.

But this is just my experience from the past promotion.
Based on conversations here and on other forums (RFD, Reddit), there wasn't much issue in the past but seems the current ongoing promotion is having a lot of troubles for the customers.