The earliest schedule would be: Nest completion on 12 April, female laid 3 eggs 12-16 April, incubation began 16 April, hatching on 20 May, young leave the nest 19-23 June.
The latest schedule would be: Female began incubation 19 April, hatching on 23 May, young leave the nest 22-26 June.
I talked to a friend in northern Indiana today. He said he had a Cooper’s Hawk nest out his window with chicks in it.
He also noted it has been a very mild winter there with no snow and it was 73 F the other day.