Glad I found this thread. Last month I upgraded my Amex Business Gold to the Amex Business Platinum (under the 50K + 50K points reward promo). I don't have any travel scheduled before the end of the year and was able to purchase 4x$50 Delta egift cards to use up the $200 airline credit.
The charges posted to my account yesterday, with the 4x$50 credits posting today.