I would think it really wouldn't matter that much, generally. But, it seems that a lot of them will put it off until summer, I have noticed that in later summer the new buses will arrive at depots. I live pretty close to one, and that's the way it seemed to me. Then, early autumn they will get around to sending the old ones off. I tried to convince my wife last year that we should buy a bus that was only a few blocks away, but we couldn't come to an agreement.