Integration

Hello everyone! We have some teenage Heritage Rhode Island’s that have been separated in a dog kennel side by side with rest of our flock for the past 5 days. I really want to integrate them as I have the next 4 days off to monitor them. Would it be possible to start this today? Or should I wait a bit longer? Also, do I HAVE to do this process at night or can I just open the kennel and monitor? Thoughts ? These teenagers are HUGE so I’m not worried about their size. The chickens of our existing flock aren’t too big of bullies either.