Synchronisation editor dynamic master

Hi.

I have a question regarding best practice when using the sync editor in our environment.

Basically we have an out-the-box sync project for handling synchronisation between 1IM and AD. Up to now AD has been the master, but we are moving towards 1IM becoming the Master, with caveats.

My question therefor is: What is the best approach to accomplish this dynamic approach

We would like to use a field in AD to establish who the master of the record is, for example if the employeeType = "1" then 1im is the master, if employeeType="2" then AD is master.

The only way i have found to handle this is by creating two mappings(with conditions) for every single record, but this feels very "clunky" hence asking the question.

Is there another way, at a higher level, in the project configuration, whereby i can specify who the master between the two connected system will be dependant on a specific field in the record? 

Looking forward to your response.