Vintage Omega help ID, history

Hello,

I’ve recently purchased this watch and I’m looking for some help with it’s history, eg which gender was this watch marketed for, is there a particular type or model that is associated with this watch?

In my research, I’ve found that the movement is from 1916 and the case serial puts it at 1920s. Is this common? Or do you suspect the movement was re-cased? Lastly, any comments on the serial number being on the back of the case vs. the inside?

Any additional information is much appreciated!

Thank you for your help and time

The movement serial number dates from 1920/21. The case is original Omega and the canard hallmark is for silver 925

Thank you very much for all the information and such quick responses.