I guess the lesson to learn is that if you want to stay in a specific hotel, you should always book in advance.

For me, it doesn't even show availability as a diamond guarantee and in Hyatt's T&C it says that guaranteed availability does not apply in times of high demand such as conventions so you may be out of luck. The alternative is a HP: http://duluthgwinnettmall.place.hyat...lace/index.jsp