Where do all the lacewings go?

Well, I can now tell you that the local lacewings spend the winter inside the door of my noticeboard at the nature reserve. I opened it to change some notices today and found about 50 lacewings, 5 spiders and a few ladybirds living it up behind the door frame. These are all green lacewings, despite some looking quite brown, but I'm not sure they are all the same species.