A Hibernating Butterfly...and a late one!

Fairly recently my brother discovered a Small Tortoiseshell hibernating on the underside of his fold-up table in his bedroom. We are taking great care not to disturb it and keep it safe. When the table is folded it just flicks the edge of its wing so we keep it open most of the time. We look forward to it spreading its wings and flying away in the spring.
Also, there has been a Red Admiral flying around the garden because it is still warm. We are worried that it won't find a place to hibernate before Winter comes.