I had run the similar amount on AMEX HHonor before the drug store bonus category went away in May. Paid the CC directly from BB. I routinely pay both husband's and my AMEX cards from BB Never heard a blip from AMEX.

Granted, I never pay with a round number and mixed up my payment sources to any CC, i.e. from BB and linked bank accounts.

The paranoia some folks have on paying AMEX from BB is completely groundless. I am reasonably confident there is no flag in place to detect such and why should they?! If at all, the flag should be at the purchase point - not allow cash equivalent being purchased and earned points, and NOT at the BB front as BB is by no means the only vehicle to unload the cash equivalent. It is just the most popular and the least effort.

The key is to make your transaction activities as "normal" looking as they can be, such as your bill pay hardly would be $1500 even as an example, but with random numbers. Spreading your loads in random days other than the first 5 days of the month. Pay your bills in random fashion both days and amounts. Having a few hundreds to a couple thousands sit there for a few days before clear them out should also help. As this is a normal user would normally do.

Of course good record keeping is a must if you want to be on top of what you are doing.

If you have double-paid a card (one from BB and one from linked bank account or autopay by accident) not to worry. Either use up the credit in coming months or ask the card company to refund the overage. Citi even would ACH the money if you provide the bank info.