Solution : https://service.sap.com/sap/support/notes/160524 (SAP Service marketplace login required)
Key words : 
generate error v1042 'sales document &1, additional key words co28, collective availability check, avoid blocking problems, sales order, special development, assembly orders, production orders, assembly order, update program
Related Notes : 
       
| 135262 | Update sales order during collective availability check |