Solution : https://service.sap.com/sap/support/notes/336496 (SAP Service marketplace login required)
Key words :
additional key words icnv, simply appending table fields, partial data loss, rare cases due, abap report rsscd900, converted change documents, respective individual documents, structure change causing, individual table fields, logical cluster table
Related Notes :
| 338968 | ICNV in the upgrade - cluster tables |
| 141465 | Conversion of tables EDIDOC & CDCLS, Release 4.5 |
| 91710 | Additions upgrade to 4.5A |
| 19466 | Downloading SAP kernel patches |