Gila Bender, that's an interesting distinction. I ran off to look at my M&P from January 1947 and found a situation that is sort of in between. The S prefix is left and the serial number pushed right, but the numerals are a little spread out. That leaves the first numerical digit right where the lanyard loop would be anchored.
As a nit-picking collector, I will start thinking of these as the "Lanyard non-accommodation transitional" models.
