At four months going into a quarantine he would be five months coming out. At the beginning he would be coming into his maturity. Give him a few wees of through the wire introduction and he would be raring to be in there. Of course the hens would want to teach him manners. If he has room to retreat to try again another day to win em over, all will be good. There is a protocol in quarantine that calls for putting a bird from your flock in with him about half way through the four weeks. That allows for you to see if the new bird is carrying anything infectious to your flock. That would mean you have to decide which one is to be the sacrificial lamb. However, they can take the four weeks alone.