The early years was especially remarkable because fake rolex watches there were many different models in such a short period of time when compared to the later years.I believe the reason for this is that the Rolex Watch Company (RWC) was experimenting with the submariner and that goes a long way to explain all the above.
The general consensus seems to be that Rolex introduced the Submariner 6204 to the world at the 1954 Basel Spring Fair and therefore this must have been the first Submariner produced by replica cartier watches. The Rolex Research and Development department must have been processing these watches many years before official introduction, and the Rolex Submariner appears in the underwater documentary "Le monde du silence" in 1953. Thus IMHO the replica iwc first Submariner to be produced by RWC was the Model 6200. The younger reference number adds substance to the logic.