Obviously proprietary data to Amex. But if you establish a history in the past you could spend 1.5 times your highest billed and paid on time. You say you want to do this next month so you will need to push a payment to amex and let it clear. No matter what anyone says or tells you on flyertalk you have the signature qualifiers for a bust out fraud. So to push your payment give it plenty of time to clear and settle with Amex