I've had dealers argue with me that the compliance date is more meaningful these days when there are long build/delivery times, but I bet if I was to try and sell the car back to them the build date would suddenly be important. My late 2011 bought Santa Fe had a build date of April 2011 on all my paperwork and when it had it's first service I was shocked to find it was actually built a year before....I got a free service out of the ensuing discussions and not much more.