Hi,
As Raja commented might be a good idea to test first using one interface. It does not matter, if you are thinking to use dual- or single-stack in PI 7.31 ( or already are in PI 7.31 dual-stack), you can convert objects into ICO objects (AEX objects). There is a migration tool available in PI 7.31 SP07 (works on dual- and single stack). Read more from sap help: Migrating Directory Content (New)