Solution : https://service.sap.com/sap/support/notes/447451 (SAP Service marketplace login required)
Key words : 
additional key words mrp run, basic finish date moves, basic finish date, lead time scheduling, -house production time, order start date, attached program corrections, planning run, program error, planned order
Related Notes : 
       
| 632951 | Basic date in planned order incorrectly adjusted | 
| 480472 | Convertng plannd orders:Basic finsh date by 1 day too early | 
| 438291 | Planned order (Conversion): Scheduling type with times |