French M51 Helmet question

Okay, I realize this might seem out place, but I don't have any other forum to turn to and, besides, this is the 'general' section of this forum.
That said, I do apologize if this bugs anybody.

I have two French M51 helmets, both advertised as 'originals'. One from 1954 (stamped inside the top of the helmet) with swivel bales ... and one from 1962 which has fixed bales.
Though there are some differences in the slope and front/back brim, the French M51 looks a lot like the American M1 and those 1962 fixed bales certainly look like the earliest 1942 version of the M1.
So, my particular question is -- knowing that the American helmet switched FROM fixed bales (because they could snap off) to swivel bales -- do you think it's possible that the French M51 helmet began with swivel bales and then (evidently in 1962) tried fixed bales?
Jeff

Last edited by jeff7salter; Yesterday at 06:40 PM. Reason: added space

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