Solution : https://service.sap.com/sap/support/notes/603874 (SAP Service marketplace login required)
Key words : 
call transaction /sapapo/bop_result, checked request schedule lines, execute backorder processing, source code corrections, requirements date/time, /sapapo/bop_update, schedule line, initial date, update results, postprocessing' mode
Related Notes : 
       
| 592523 | Confirmed schedule line not generated in OLTP system | 
| 375193 | Backorder processing: Composite SAP note on posting |