Solution : https://service.sap.com/sap/support/notes/317994 (SAP Service marketplace login required)
Key words : 
additional key words sis, mm purchase order number, stock transport orders, attached source code, update behavior occurs, statistics update, online update, update group, billing documents, program error
Related Notes : 
       
| 386263 | SIS: No header STAFO during statistical setup deliveries | 
| 204130 | SIS update: Collective note | 
| 174134 | SIS: Collective note - reorganization | 
| 140208 | SIS reorganization: Deliveries without order reference |