So that means litterly that my if I am issued a card, my parents can use up to a sum of say in this case 20 000 krones a month, then at the end of the month before the end of the 30 day billing cycle, transfer 20 000 krones to my account so that when amex perform their deduction I remain on the same sum I was before. say if my account is 0 is remain on 0. Would this work?