no special instructions. when aaa books your disney vacation the charge on your visa still says wdtc or whatever just as it would if you booked yourself direct. then when it goes on your bill it is recognized. It will be part of the regular list of charges but there is a section of the bill that says what is at what interest rate and will list it there. Some people say their payments have gone to this first but mine didnt. (meaning that they then were charged interest on part of their regular charges). Room only's do not qualify for 6 months no interest though.