I bought our Delta tickets this morning for October and used my gold business card for the purchase. Benefit? double miles. In our case, 1000 miles. After closing out the delta screen I went to my email to retrieve my ticket receipts. Further down on the page was a mileage bonus promotion for 5X the miles on my platinum card. I enrolled and attempted to enroll the gold card but the promotion was for platinum only. I called Delta and they very graciously took the charge off of the gold and put it on the platinum. Yeah! 2500 additional miles for my purchase. Thank you Delta.