BAPI/fn module to unassign outbound delivery from shipment

Hi,

I want to be able to unassign an outbound delivery from a shipment, from within my own bespoke development. I want it to essentially replicate the functionality you get when you unassign a delivery from a shipment with VT02N by "dragging and dropping" the delivery down to the "deliveries not assigned" window pane and saving the shipment.

Unfortunately I cannot find an appropriate function module/BAPI to do this. Ironically there is SD_DELIVERY_ASSIGN_TO_SHIPMENT to link a delivery to a shipment, but not the other way around.

Im currently investigating and testing the use of function module SD_SHIPMENTS_SAVE to see if this will give me what I need, but this is a "last hope".

Any other suggestions?

Kind regards,

Jon-Paul.