I reserved two Fs previously, one with cash and the other with AC, only the cash one eligible for upgrade. At the very beginning, I was able to get in 1A without paying anything, however, it was fixed after a few hours and I was not able to get back in any more. So basically at this moment, I guess you will just have to pay with cash that costs around 5000 USD in total, however, I still think it is a decent price. You will be able to get a few bucks off with Amex.