Solution : https://service.sap.com/sap/support/notes/62426 (SAP Service marketplace login required)
Key words : 
additional key words subsequent settlement, volume-based rebate income posted, volume-based rebate income, creates incorrect settlement amounts, volume-based rebate, vendor business volume, correct settlement amounts, tax code v1, tax code v2, tax jurisdiction code
Related Notes : 
       
| 40147 | Collective note: Subsequent settlement (Purch.) Release 3.0 |