Well I wouldn't have guessed you are in one place! That's completely different from my experience with myself. I can go to bed hours early, still fall asleep p

Well I wouldn't have guessed you are in one place! That's completely different from my experience with myself. I can go to bed hours early, still fall asleep pretty quickly, and essentially just sleep through to the waking time of my latent schedule. Contrast with staying up an extra few hours will cause my waking time to move forward about 20-30 minutes. The main way I can move my schedule earlier is to make myself get up earlier, and then stop myself from taking a nap in the middle of the day. That's of course modulo artificial light and being indoors. I haven't really tried to reproduce the effect of camping indoors, but I think the exposure, temperature change, and nature's activities contribute more than the light level. Indoors, I can generally continue sleeping just fine with direct sun on my eyelids.