Solution : https://service.sap.com/sap/support/notes/362648 (SAP Service marketplace login required)
Key words : 
additional key words interest calculation method, interest calculation method act/actp, calculation date relative, attached advance corrections, calculation date, date update, 'adjusted' rule, system updates, regular intervals, system calculates
Related Notes : 
       
| 394782 | FIM: Update using due date: Incorrect period start | 
| 312475 | Incorrct accrued interest calculation for act/actP | 
| 191374 | Interest calculatn method act/actP - wrong amounts | 
| 167080 | Incorrct accrued interest calculatn for long coupon | 
| 139635 | Interest calculation method act/act - Zero bonds | 
| 109587 | Interest calculation method act/act |