adding a new queen

[drewgrim]

i have a theory after looking at what hives have survived this year so far. i added a queen this past august to a split that i made and that hive is doing fine. the hive with the old queen looks like they might have frozen. is it a good practice or idea to add a new queen in late summer? seems like she would be a more aggressive layer than the old queen that has been laying all summer?

[Wally]

Many commercial beeks requeen all their hives in early fall.