Citibank has a card that offers 10% back on award mileage up to 10k a year. The Barclay card that used to be US air offers the same thing. I was told today that the rebate is 1 per passenger, not per credit card, so even though I now have a new card that offers 10% back I get no benefit since I already have the citi one. I can't find this limit on any of the info from the cc company. Does anyone know where to find this condition?