I gave my broody just over a week to make sure she was serious about being broody. Popped 5 chicks under her at 2 in the afternoon (most wait until after dark. My broody would adopt a Great Dane) and the hen did all of the rest of the work. My nest boxes are ground level so she used the box until about 4 weeks when she moved the chicks to the perch.
She was never separated. She kept safe distance from other flock members and the babies at all times. Returned them to coop each night to sleep (they free range) and has been their protector in every way. If they get knocked off the roost at night, she makes room on the roost so they can get back up.
To me..... it’s the only way to go. She’s gradually integrating into the flock currently. If the other hen pecks once to get space she’s ok with it. If hen starts being overly aggressive, momma hen opens a can of whip’em good and life goes back to normal.