can anyone please confirm if this watch is a push fit or screwback

I have tried both to know avail

many thanks

 

Snap back. You need to find the correct blade size to start opening the caseback.
if you're not sure, get a watchmaker to do it properly.

 

Lovely piece btw. I think I'd find someone to do a lume restoration.

 

With a thin sharp knife it should be easy to open this snap back.