I think it is mute anyway. I have never been asked for any AP when checking in on an AP rate. I have never been asked for the postcard when checking in on an postcard rate. And before anyone says that WDW has it in the system about you having an AP that just wasn't true in my case. I had the vouchers, not the real AP, so WDW had no idea who I was. I hadn't activated it yet and they had no info on me to know I had an AP. I think the CM just sees the words AP holder discount on the reservation and goes with that. On my reservation there was the words AP passholder rate but that is only because I called CRO and got an AP rate. CRO has no idea who has APs and who does not. There are many folks that make the reservation before even purchasing the AP or voucher. So the hotel CM only goes by what CRO puts in the computer. I've never been questioned about my discounts when checking in. As far as being of legal age to reserve a room you can put anyone you want on the reservation along with someone of legal age. One year they had myself and my 3 y/o DD down on the reservation. I don't know why they did this but she was on it. You can put yourself and the passholder's name down on the same reservation. When you check in, IF they even ask for the AP, then the holder will be on the paperwork but you are paying for the room. An AP holder can reserve 3 rooms at a time. There are many times that they are getting the room for family and friends. As long as the AP holder is there at check in then the other rooms can be put on whomevers credit card that they want. I personally just called CRO and asked this and they said "NO PROBLEM. As long as the passholder is with you at check in you can use it. It doesn't matter if it is a child or adult. Just make sure there is an adult ALSO on the reservation and you are all set." Now I haven't tried this yet as we all have APs but my AP expires after our next trip in May. My DD's child AP doesn't expire until next October. So I decide to go on another trip then I will certainly use her AP to get a good rate if I don't renew mine. I highly doubt that Disney is going to quibble about using a childs AP, especially when every offer I have seen never says it is for ADULT AP holders only, just AP holders.