Twilight is fading now and another check of the white LEDs suggests they’ll be quite adequate for the job, so I’ll look at getting another strip (it won’t need to be anywhere near as long this time) for the warm room and put them in the ceiling. Initially I was thinking that I’d just have white for the warm room, but in fact I think it makes sense to have red available too, so if I’m doing something that involves moving between the scope room and warm room and I want to maintain dark adaption then I can do so.
Making that decision means I can now get on with lining the warm room ceiling. In fact given that I still have some clips left and a few bits of the aluminium section to use as spacers, I could probably do the entire thing and get on with painting the warm room too. Not sure I want the same colour as in the scope room though.