Split outbound delivery by Purchase Order number

Hello!

In our business process, few stock transport orders may have same supplying and receiving plants and same material. Only the batch would differ. Now, when outbound delivery is created in background, one delivery is created for all the STOs.

The requirement is to have 1 OBD against 1 PO/STO. I got a fair idea that the concept is called Delivery Split and can be handled with ZUKRL field. Can anyone please help with the include or FM that needs to be modified.. Note that this is for deliveries created off purchase orders. Any further details would be appreciated.