I have 9 RIR pullets that are just over 7 weeks of age. They have been in the coop/run for over a week. The coop is elevated over half the run, and accessed up the ramp. The 2X4 flat-side up roosts are in the coop. The chickens stay in the run 24X7 and just huddle together in a corner at night and do not go up the ramp and into the coop to roost at night. Will their instinct to roost eventually kick in and they'll start going into the coop at night to roost?