The order is whatever they think will be most profitable. Usually that meant high-spec California first, but as they open new factories, that could change.
California deliveries are usually toward the end of the quarter, because the cars have less shipping time to reach the destination. California is normaly getting delivered the last 1/2 of the month at the end of the quarter, just like other states. The difference is, those other states get assigned vins first when they are further from CA because the car takes longer to ship there.
TL ; DR, no CA is not usually first, tesla tries to deliver as many cars each quarter as it can, and that normally means the farther from CA you are, the sooner you are assigned a vin, even when deliveries tend to all happen at once.