OD Replication Traffic Issue

Quick question;
I have a master and three replicas on one main campus where the buildings are linked together with fiber. Across town, I have another master. I would like to demote that remote master to a replica of the master at the main campus. It’s so I would just have to maintain one master, and when, on the small occasion that a user happens to be at the main campus, they would be able to sign on and get their stuff. The link between the remote school, however, is a T1 line. I am concerned about the amount of replica traffic that would be transversing the point-to-point. I would point all of the clients at the remote site to the new local replica, which is also serving DHCP and DNS at the remote location, but I am concerned about unnecessarily bogging down the connection between buildings. Any comment on how much traffic is generated? Is what I want to do worth it?

P.S. I have my master set to update records when changed. I notice in the log that the master does a check and sync of its replicas every 5 minutes or so though. This master was an original from the 10.4.2 days and I have upgraded it along the way to version 10.4.8.

Thanks for any input/suggestion!
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