while it's a nice gesture, WDW does not allow you to change the lead guest name on a reservation so it's non-transferrable. If you cancel those rooms, they may or may not be available for the next person who calls if you coordinate it like those do with dining.
If they are BRP rooms, you probably would have your name on all reservations because of how the system books so that may be the only way around it. However, I think that could create alot of problems. If Disney thinks that AP holders are booking the max 3 rooms and then "giving" them to other guests, we will see policy changes just like when people were booking multiple CRT reservations and selling them on Ebay.
Not saying that you are in any way meaning to do that, but I see trouble ahead if Disney suspects it.