I am lucky this winter that I dont have any cats that want to go out - but when I do, I sit and freeze!! I generally have cats that dont like the door being shut, so it isn't, and I sit with a blanket over me. There is generally a cut of of 9pm though, although Rolo often demanded to go out later than that last year - he was always told just for 10 mins, but often didn' listen. I found that males were much worse at going out later and staying out, I have really only had one female that wanted to go out after 7pm and she only ever stayed out for 10 mins, the rest have all been rather sensible - although the current two take it a bit far, they dont leave my room, much less go downstairs and ask to go out!!