The older ones are ready to go when you are, you still do need to do an integration period if you haven't already done so.
The younger as well.
Just as a point of reference I brood outdoors with the aim of having chicks fully integrated and in the coop with the adults at 4 weeks. If you have ample space and feeders and clutter to break up the area it can be much easier to do it sooner rather than later, as small chicks are less of a threat to older birds.