30 days? They've all been vaccinated. Why 30 days?
It's possible when you meet someone and shake their hand you could get the flu or some other disease if they have the flu or some other disease. There are a lot of parasites an diseases that are not vaccinated for. When two new chickens meet it's possible they could give each other a disease or parasites if they have a disease or parasites. Some people quarantine new chickens for a month before they mix them with their flock to check for these diseases or parasites. Not everyone quarantines and many that think they are really don't do it right. You can write a lot about quarantine, but since yours have already mingled it's too late for it to do you any good if there was even a need to start with. It's water under the bridge so don't worry about it.
Thanks for giving the age of the two groups, that helps a lot. Since you are dealing with living animals no one can give you guarantees as to how they will behave, but you should be better off than many people.
Since they are all mature, they have to work out their place in the pecking order. That often involves pecking or some form of fighting. Sometimes that gets violent and sometimes you may not notice it happening. How much room you have inside and outside is important. With them free ranging you appear to have a lot of room outside which is good. That large coop helps too.
I don't know where you are located so I don't know your time zone. You've probably already managed your first night. If you did lock them in the coop together and there is still time my suggestion is to be out there at daybreak to see how it is going. They my be fine, you may need to let them out early. Or maybe not.
There are different ways you can try to integrate adults. Some people would just put them together and see what happens. Sometimes that works, especially if you have a lot of room. Most people on this forum don't have that kind of room.
If it is too violent for that to work, housing them separately but where they can see each other through a fence for a while can get them used to each other. Letting them range together during the day but sleep apart for a while can ease the transition. Having different and spread out feeding and watering stations can reduce points of conflict. For people that keep them in runs adding clutter to provide places for the new ones to hide under, behind, or over can improve the quality of that space. If you leave them locked in the coop when they are awake clutter in the coop can help too if they are violent.
At some point they will have to work their way into the pecking order. As long as no blood is drawn or one is not trapped on the ground with another standing over it pecking at its head I pretty much let them work it out. It is a judgment call as to how much is too much and you need to intervene.
I wish you luck.