Syrte
·Hi S. I got curious of your point as I'm not knowledgeable about these watches so I researched a bit and saw this
https://www.hodinkee.com/articles/a-historical-look-at-the-blancpain-fifty-fathoms-live-photos
Okay in fairness to Hodinkee they're not saying outright that the BP Milspec 1 is a French navy diver. They just talk about the early development of the BP FF, and then they post a Milspec 1 picture without clarifying the connection. So it's just fuzzy, or a bit sloppy, but not outright inaccurate.
What is inaccurate though is that dealer's label in the picture posted.