We can now see that it's a BSA, I have never seen rear ends like it.
My best guess would be mid 1950s. I think the BSA "dynohub" was 1954.
BSA did use odd components towards the end.
Keith
Forgot, the handlebars are far too high, the rod brake adjustment at the front has 2 vertical nuts, the rods are locked by a coil spring inside each nut, very neat BSA fitting. Just undo about 2 turns.
The Sturmey archer gear trigger has the wrong spacing for a BSA hub, but might be better than nothing. The hub gear will probably slip in high gear anyway.
Keith