It looks a bit like 661 Pseudatemelia flavifrontella or 660 Pseudatemelia josephinae, and the size would be about right. If it is it looks like a good record! Interesting to hear what Dave says.
Looks like the dark form of Ash Bud Moth, Prays fraxinella. Sorry not to agree with Adam's more exciting suggestion!George
Funnily enough, you're spot on there George! 2 hours of sun today must be getting to me...
Thanks both. I used to get a few of these, several years back. Obviously getting rusty and not just from always being out in the rain.
Yes, Prays fraxinella f. rustica, although there is speculation over whether some of these dark forms are actually a separate species (Prays ruficeps). The jury's out on that one as far as I know!