If it was me, I would turn em out on a day that I could be there at dusk. They should return to the coop as the day winds down. But they sometimes seem to have a problem figuring out the door/ramp to get back in the coop, and end up piling up next to the door or a corner. If you are there while they are milling around, you can kind of guide/shoo them into the coop. Once it gets so dark they will just call it a night and settle in where they are, making them a easy target if you don't get to them first. Eventually they get it figured out, but during the learning phase you don't want to also be teaching you local predator population that happy hour starts at your place at about dark.
