This is how is is SUPPOSED to work, but I wouldn't count on it! We never received tickets or a reminder (maybe because we were on PLA rotation on the Western carribbean so our Character Breakfast was the morning after Pirate Night). Our server called our room about 15 minutes into our breakfast time to ask us if we were coming - we rushed over there, but we still missed Mickey and a couple other characters. The head server tried to get Mickey back for us, but couldn't work it out. Fortunately, we go to WDW regularly and have done many character meals so DS5 wasn't too disappointed - he said "I'm sad we missed Mickey - but we'll see him next time!".
pdarrah