Damian: I don't have a Citi Cash card to test it, and I didn't see anything on the site the addressed the use of an AAdvantage debit card (or other Visa/MC debit card). However, my hunch is that as long as they allow you to link the card and waive the "loading" fees (and this is a big if), you should be fine. Your card certainly can't charge you a cash advance fee, given that the cash is being withdrawn from your checking account.