The chrysalis has gone much darker and if I stand really quietly and watch I can see it moving as things happen inside! He also moves more if I shine a torch on him, so I think he likes that, but Lloyd said he's saying "turn that light off!" I'm really not sure how long he's got to go like this, but he's in the living room so if he emerges overnight the door is shut so no dogs can get him. I thought it was probably the safest place but the room is darker so if anyone thinks he needs more light let me know and I can move him.
I can see the colour of his wings through the chrysalis now, clearly red.