I never worked as a CM, but I think it is more about when you come, and what they have available. Disney uses a priority seating system - not resvervations - so they don't hold a table for you. That way, they maximize the number of people thay can serve, and there are no vacant tables while their are people waiting (which is really great if you are one of the people waiting for a table). When you show up, you get the next available table for the number of people you have (after those who are ahead of you who also have a PS for the same time). Knowing Disney, they probably do keep track of when you made the PS, and whether or not you are like a "special" guest or not (like a celebrity, or a bride or something) but I'm not sure it affects the seating very much. If you miss your appointed time though, you may have to wait for a table considerably longer, your best bet is to plan on showing up a little before the PS time (It always takes longer to get to a place than you think it will!) Hope this answers your question!