As Becky says: wait till the season begins. In the last five years at our park something always happens and sites become available. You are talking about a SENIOR population mostly. The coasts are definitely harder to find spots than in Central Florida but still I think you will find something: maybe not the best site but something. Good Luck
Have Fiver will travel with little or no notice at all. I do need to stop at rest areas now and then:)