Reintroducing non-master ACM to network


I have a ACM that had been taken out of the network for awhile and would like to put it back into the network. This was and still would be the secondary acm. The master has been on the network the entire time. The secondary is configured as it was when it was removed from the network.

My question is what happens with any of the changes that have been done to master. Also what happens to any configuration settings on the secondary that do not match the master. My hope and understanding is that the secondary would take on any changes made to the master.

Thanks you for any help.