Solution : https://service.sap.com/sap/support/notes/174529 (SAP Service marketplace login required)
Key words : 
fiscal year change data, commitments carry forward prior, additional key words, conversion program rffmcftr, carry forward, data conversion, carried forward, symptom documents, reselect documents, conversion
Related Notes : 
       
| 174518 | RFFMCFTR: incorrect documents FCABP NOT FOUND | 
| 101778 | Conversion of FM data structures as of Version 4.5A |