Suggestion: spend additional $2500 on the Blue Sky card. American Express has already given you the 2,500 Membership Rewards points that you could earn by putting these transactions on the Green card. It sounds as if you can do this in less than a month. You will then have 7500 points, sufficient to redeem for $100 towards, for example, a hotel stay. Cash out. Put the card in a drawer or cancel it after you have the Starwood card.