I just dug down into my Experian Report, and for open Amex cards, I am an AU on 8 cards. On my wife's Amex account, I am an AU on 2 personal and 3 business cards. On my Amex account I am an AU on 2 personal and 3 business, although the AU on 1 personal is from a few days ago. Regardless of how it works, I am an AU more than 1 time and more than 1 card, but it is not showing up a crazy amount of times. So it might show on your report, but not more than 1x per card account.