Solution : https://service.sap.com/sap/support/notes/520561 (SAP Service marketplace login required)
Key words : 
standard lot-sizing procedures fixed order quantity, planning reporting point planned materials, 'reporting point' lot sizing procedure, 'reporting point' lot-sizing procedure, central material master record maintenance, goods issue processing time, generates unnecessary cif transactions, fixed order quantity, <matlocx> type /sapapo/cif_matlocx, -lot order quantity
Related Notes : 
       
| 619973 | R/3 - APO integration and Customizing changes (document) | 
| 551124 | APO: Finite scheduling with MRP heuristic (documentation) | 
| 496149 | Selecting changed products or location products | 
| 459694 | Finite scheduling with CTP or SAP_MRP_002 (documentation) | 
| 402247 | Reorder point planning in APO | 
| 143314 | APO - R/3 Integration in Production Planning | 
| 44410 | Integrating cust.-specific fields in matl master |