We were offered the 25,000 points almost every other month in the past. The 25,000 point offers eventually stopped. Then, we realized that it is probably well-worth going Plat (which it is, the benefit we've gotten so far has already way beyond offset the fee). I called and told them about the numerous offers I've gotten in the past but was told that there's nothing they can do about it now as there is no such offer at this time...yada yada. Went ahead and applied anyway, when we got the card I called CS again and was transferred to MR. I said that we were definitely targetted and if they can check their record of the numerous mailings/offers that were sent in the past. They said they'll investigate and within 2 weeks, 25,000 points posted in our account. So, from my experience, I don't think you have to worry about the expiration date. Although, nothing is guaranteed and I may have just gotten lucky. You never know what Amex will and will not do.