Auto change shipment status on PGI

Hello,

We have a scenario where we need to update shipment document status to 'Shipment end' (7), when all the deliveries under that shipment, are PGIed.

This updating status should be automatic.

Shipments are created with VT04. Then subsequently shipment loaded. When the shipments leave physically from location, the PGI is posted in delivery. This should trigger the status change to 7 for shipments.

How to set this up?