I have bought many ZEDs on AA. You must first purchase the ticket on the ID90 site. Then you have to use the myidtravel site to create a listing. On the myidtravel site there is a link for existing tickets or something like that. You need to select that and then enter the ticket number and it will take you through the listing process. It’s all spelled out on flyingtogether. If you select other airline/interline travel and then select AA from the drop down. It will provide the links for id90 and the links for myidtravel... also there’s no 24 hour limit. We did it last minute all the time.