New development. She's always hung out with the rest of the flock and shared the roost, although now that I think about it, she was usually kind of a lone ranger on the roost - all the others were usually clustered together and she was off by herself at the opposite end. Maybe she has just gotten too heavy to get up on the roost - it's end of summer and in addition to free-feed crumbles, they have plenty of greens in the chicken yard and I usually also let them free range for a couple hours. I'll just monitor it I guess and keep tossing her back in the coop. Otherwise, she will likely get eaten by some night predator. I'll try to watch the evening 'return to coop' shuffle and see if she is just missing the automatic door closing, or if the flock is preventing her from getting in, or what the deal is. Not this evening, though, we'll be gone. Kind of a mystery...