Yes its hard to date this pic, I think it maybe late 68/early 69, Not wearing braces was not a big deal, the turn ups are a bit strange, I do not think the Girls hair is a grown out feather cut, I remember girls wearing that type of dress when i was in school in 68, its just what any girl would have worn. Going back to the turn ups, We would just roll them up, trying to get the turn up 3 quarter of a inch.. to one inch. Think I did know something about the provenance of this photo, but I can't bring it to mind at the moment (must be getting old)! I'll have a think and get back to you. What I will say, though, is that the girl's shoes look later to me. Brideshead, wasn't your girlfriend wearing something similar in your autumn '71 photos?