I've been unable to find the answer to this question, so trying here.
There is a column called "ChildLevelNumber" in the view of each parent-child hierarchy (view usually called mdm.<EntityName>PC)
When moving a member between the nodes in the hierarchy that level is set to -1 and then can be corrected by some process.
I am guessing that it is done by this SP: mdm.udpHierarchyMemberLevelSave but how is it called?
So far I've tried validating model, running business rules etc - no luck.