Solution : https://service.sap.com/sap/support/notes/954793 (SAP Service marketplace login required)
Key words : 
system offers web dynpro objects, component bc-upg-na, downtime-minimized import mode, basis support package sapkb71006, spam/saint updatechange history- 18, profile parameter rdisp/bufrefmode, solutions spam/saint version 0026, unnecessarily long background job, web dynpro objects, spam/saint update
Related Notes : 
       
| 1142128 | Note Assistant: Obsolete notes are incorrectly deimplemented | 
| 1137503 | Secondary index for table REPOSRC | 
| 1126127 | DB6: Deferred Table Creation and Row Compression | 
| 1086728 | Unreqd deletions in SPAU comparison after importing SP/EHP | 
| 954792 | Known problems with Support Packages in SAP NW 7.1 AS ABAP |