Use the migration tests from CAM-3826 and run the tests with version 7.4. The processes should deploy with 7.2 and execute with 7.4.
The migration tests are necessary because of changes in legacy migration code (see CAM-3856).
CAM-4229 Extended Process Instance Migration test infrastructure
CAM-3856 I can use asyncBefore and asyncAfter on the activity wrapped in the multi instance body