Are you referring to the
AAA Diamond pass? If so, those cannot be bought. You get one as part of your vacation package when you book through AAA.
They are nontransferable and void if sold (it says so right on the pass).
When you book your AAA vacation, you'll get a pass for the year in which you take your trip. For instance, last year (November 2012), I booked a trip for January (2013). When I received my documents, I received a 2013 pass.
My guess is that you will need the correct year's pass in order to use it. They may make an exception for those whose trip crosses from one year into the next (i.e., visiting over New Year's).
However, rest assured that when you book your trip, they'll send you the correct pass. Therefore, there shouldn't be a reason that you would be showing up there with the wrong year's pass.
And if this is not the pass you're referring to...just forget everything I said.