It's unlikely to have been tailored to a specific market at that period in Heuer's history. Potentially it could have been at the request of the customer, if the pilots had no need to time to 1/5 of a second, just the nearest second.

Given the wear and tear generally, particularly on Arno's watch, and the relative whiteness of the bezel, I still think it more likely that the bezel has been refinished. Obviously, it's much less fiddly to restore just the major markings and these are more likely to survive at least partly intact and provide a guideline for the restorer. Both watches may have even come through the same route.