Solution : https://service.sap.com/sap/support/notes/110094 (SAP Service marketplace login required)
Key words : 
function 'read master data', additional key words co01, swapping sequenceread master data, explosion alternative sequences, sales order, assembly order, incorrect operations, order maintenance, sequence swap, assembly processing
Related Notes : 
       
| 114729 | VA02: Termination when changing the configuration | 
| 94971 | Production order:RGEKZ is missing after reading BOM |