Solution : https://service.sap.com/sap/support/notes/306428 (SAP Service marketplace login required)
Key words : 
sar sap b2b procurement / sap crm upgrade, os/390                    system unix services- wp211/gdnt, additional key words upgrade guide, general/r3server/abap/note, windows nt- wp211/gdunix, sap bw release 20b, windows nt- apo310ca/gdunix, sap apo release 30a, windows nt- apo310ca/gdnt, windows nt- bw20b/gdunix
Related Notes : 
       
| 504959 | Upgrade Assistant on z/OS | 
| 436181 | Enhancements to upgrade to SAP APO 3.1 (Support Release 1) | 
| 336428 | Error when starting PREPARE from CD (4.6C SR1) | 
| 302309 | Additions Workplace Server Upgrade to Rel. 2.10/2.11 |