Originally Posted by
canadou
Is that from your experience with the 10% offer? Quickly called AMEX to ask last week and they say it wouldn't affect the offer, but still apprehensive to proceed not having written confirmation from them since it's quite a lot of money.!
Yes indeed, I used the 3x payment on those tickets, and received the ~400€ cashback as expected after reminding them

(It works the same way as miles: you get all of them on the month you bought your ticket, even if you pay it in 3 installments)
Now, I'm waiting for the 50% on the other tickets, that I also selected for 3 installments payment.