We have a configuration with 3 source systems. A primairy system on which we create de accounts and additional source system to add extra information to the primairy system. We named the source system so the primairy system is Ascending first and added "Source.DisplayName" as first field, but when one of the other system had a contract end date that is beyond the contract of the primairy system this contract becomes the active contact. And that gives problems because the base properties are not is these additional systems.
The sorting to the active contract first is in the code an can be lowered at the primairy contract order list so the "Source.DisplayName" is always first. This would solve our problem.