Solution : https://service.sap.com/sap/support/notes/442259 (SAP Service marketplace login required)
Key words : 
additional key words transaction, prerequisites solution note 398486, /sapapo/bop_resultbackorder processing, symptom configuration characteristics, configuration characteristics, backorder processing, /sapapo/bop, /sapapo/bop_update, class characteristics, main items
Related Notes : 
       
| 408776 | Backorder processing: Results display terminates | 
| 401255 | Interface enhancement for sales order re: configuration | 
| 400662 | Backorder processing: Configuration characteristics | 
| 398486 | Backorder processing: Configuration characteristics | 
| 375193 | Backorder processing: Composite SAP note on posting |