I disagree with that as a general statement. In my experience, round-case Soviet Amphibias most typically have the red and black dotted bezel with a luminous dot at the 12 position. The bezel in the picture above more typically belongs on the octagonal Amphiba case. That being said, this bezel on a round Amphiba case isn't entirely unknown. There is at least one in the Levenberg book (so much as that can be trusted as a so-called 'authoritative' source).That bezel is correct in round case soviet amphibias.
I'm actually looking for a no date amphibian, any pointers on nice ones guys. Thanks a million.