That's not really a surprise. After plate ZZZ999 was distributed, California made a seamless shift to the blue plates. The model year for the car that received 000AAA was immaterial to the state. I've seen several 1969 cars with original blue plates. The same thing happened about ten years later when the six digit combinations were exhausted and the next combination was the same yellow letters on blue plates but with an additional digit. In 1980 my Suburban was assigned plate 1AEK###.