OK, one more time. In 1963, all cars registered in California that had the earlier yellow background/black letter plates, had those REPLACED by the black background/yellow letter plates. So the year of car didn't matter a lick. In 1961, that VW had the yellow plate with black letters. In 1963, those plates were replaced by black background/yellow letter plates. Clear now???
In mid-1969, the car alpha sequence reached ZZZ-999, so in mid-1969, the car plates became blue background with yellow characters; with the numbers first (001-AAA through 999-ZZZ). Trucks changed in early 1971, as their numbering sequence was different (A00001 through Z99999). Those cars and trucks registered with the black/yellow plates KEPT them, as long as the car/truck remained continuously registered in CA. Same with the blue/yellow scheme and all others that followed.
Don't believe me, call Auto Club in CA. Or check many, many sources online. I knew this without having to check, 'cause it's a part of Stuff I Know.