Solution : https://service.sap.com/sap/support/notes/378307 (SAP Service marketplace login required)
Key words : 
additional key words sis, vbak         optional    pass valuei_xmcvbap, vbapvb      optional     pass valueactivate, order header - structure vbak, order item - structure vbapvb, attached source code, function module mcv_statistics_delivery, sales order data, function module exit_saplmcs5_002, sales information system
Related Notes : 
       
| 204130 | SIS update: Collective note | 
| 174141 | SIS: Collective note - Customizing | 
| 144237 | SIS user exit: no partners, schedule lines, conditions |