I don't believe this is true. Model year breaks are not specified by law. A car cannot be VIN'ed for a model year more than one New Year's Day ahead of its first delivery year. This is why Ford began deliveries to the dealers of the 1997 Ford F150 truck on January 2, 1996. So some of those 1997 F150's carry build dates as early as fall of 1995. Likewise, I remember seeing truckloads of 1995 Dodge Neons at the Belvidere, Illinois plant in late 1993.

The model year is determined by what regulation specifications the car is built to. It's up to the manufacturers to decide when they want to change. And each model line in a manufacturer's lineup will likely have different year breaks. I believe we shall be seeing 2012 Lexus LFA's on the roads long before June 30, 2011.

I wouldn't be surprised to see a few 2011 LP700-4's in the U.S., even if they are just the dealer demo units.