Solution : https://service.sap.com/sap/support/notes/542340 (SAP Service marketplace login required)
Key words : 
time-reference characteristic reason, 0a            import support package 12, 0b            import support package 5, time-reference characteristic, fiscal year variant, automatic time conversion, 0a support package 12, 0b support package 05, time characteristics individually, existing update rules
Related Notes : 
       
| 554380 | Error when updating stock cubes | 
| 523217 | SAPBWNews for BW 3.0A Support Package 12 | 
| 493976 | SAPBWNews BW 3.0B Support Package 05 |