A planning unit hierarchy contains planning units and entities that are part of the review process.
Parent/child relationships between planning unit hierarchy members affect the review process:
When you promote or reject a parent, its children are promoted or rejected unless they are Approved. The owner for the parent becomes the owner of the children.
After all children are promoted to the same owner, the parent is promoted to the owner.
When the status of all children changes to one status, for example Signed Off, parent status changes to the same status.
You cannot change the status of a parent if its children have different owners. If the children are promoted to, submitted to, or signed off by different users, the parent has no owner and only budget administrators can change its status.