Comma Butterfly?

Well I don't think that it's a Small Tortoiseshell because (according to the photo) they have white patches on their wings. The description of the Comma says that it "looks like a tatty Small Tortoiseshell". Which is pretty much it I think. And yes, I realise that the window and window frame is distinctly grubby - sorry. I was in the middle of cleaning (honest) but to clean there I would have had to disturb the butterfly and missed the blip opportunity.