Here is my suggestion,, since you do have plenty of time.
About 3 weeks before your chicks arrive, set up a box on the floor, and make a comfy nesting area. If you do get a broody chicken at that time,, she may choose sitting in that box, and stay there, trying to incubate eggs. Let her sit on a few eggs, like 4, and keep replacing them every couple days, so they don't start to develop. If your eggs are not fertile,, then just sacrifice those 4 eggs for whole duration of time.
If after about 3 weeks of sitting, your hen is still on eggs,,, then slip in chicks under hen at night. Of course do remove the eggs at that point.
Having the nest box on the floor has a couple advantages. You can open one side of box, so chicks can walk out from under hen,,, and not fall. They will feed on crumbles you place on floor, and drink some water. Then go back under mama to hide and stay warm.
You may have to provide a barrier so the other hens do not try to harm the new chicks.
I can make multiple suggestion when that time arrives.
WISHING YOU BEST,,,,,,,,,,,,,,,,,,,,,,,,
