Further update: Lattice panels and integration.
Went down today about noon, two of the hens are in the chick part. Nothing is upset, chicks are all over the run yard, roosting on a branch I have in there. Nothing chasing, or harassing. Chicks are calm. Chicks will be 3 weeks old on Monday.
I went ahead and opened up the pen. I did leave one lattice panel up in the middle, and leaned the other against the wall.
Really this has been pretty effortless. My chicks are healthy, active, and living with the big girls. A couple of points, my flocks have had chicks raised in the flock for years, and so did the other hens I bought. I have a large run 20 x 30 feet. I do have hide outs, and mini walls and different roosting heights.
I still have two water and feed stations set up, and probably will for some time, it is no big deal, and it will make sure the chicks get enough.
I am a believer in a wooly hen, and it is certainly a viable way of raising babies without electricity in even moderately cold weather. The lattice panel worked well as a one way gate. I have been raising chicks for years with a broody hen, and was rather dreading this whole deal, getting them feathered up, getting them integrated into the flock, and really it went pretty easily.
Mrs K