Originally Posted by
friedablass
1. It's possible that paying with points will trigger the credit but the better and more certain option would be to charge $300 to the card which will definitely trigger the credit and cover the remaining amount with points which is at a value of 1 cpp.
2. Existing reservations will not trigger the new $300 credit. You need to make a reservation starting today and prepay for $300 or more to get the credit. Any reservations prepaid prior to today should have triggered the old $200 credit if you hadn't already used it.
Also note that for #2, if you cancel an existing reservation and rebook, Amex would claw back the previously issued $200 credit, and you'd get the $300 credit instead. Assuming you have no plans to make an additional reservation between now and 12/31 (which could be for a stay any time in the future, not necessarily 2025) you could save $100 that way. Otherwise you can make a second reservation and claim another $300 as well.