So that's what's eating my strawberries

I have been wondering for a while about my strawberry plants. They have had holes appear in the leaves, but up until today I was blaming slugs. but I found this little critter quite happy to munch away.

I figure if it doesn't go to crysilist soon it won't survive the shock frosts that will be here by the end of the month.

Will it be a moth or butterfly....do you know?