I personally know two drivers who retired with 30 or more years in October of the year, and drew their vacation checks for the following year on their last day in the building. I took a photo of one guy flashing seven checks and smiling...
So, I would say there are exceptions to the rule that tieguy cited, in fact, these are the only two retirees I know who were in that situation, having worked enough hours to earn their following year's vacation time prior to their retirement day. And in both cases, they were paid their following year vacations with their last paycheck.