To add to this, you have to go to the gates where they scan your ticket. Don't go to the ticket both where you purchase tickets...they not only can't do the exchange they sometimes don't even know it's possible! I went last sunday and the lady at the ticket both had never heard anything about it. She even asked her manager and was told it couldn't be done. I even informed her I was told this could be done when I called disney to book our hotel, and told her the cast member at our hotel said it could be done but she kept insisting it can't be done. I thought I would give it another shot the next day and I asked at the ticket booth again and was told by someone else they could do it at the gates. They knew exactly what I was talking about when I went to the gates and I ended up getting a one day park hopper out of it! Not sure if they always do that, but they asked what type of ticket my DBF had, and he had a park hopper so she said she'd give me one too.