Solution : https://service.sap.com/sap/support/notes/543687 (SAP Service marketplace login required)
Key words : 
rules-based availability check, symptom incorrect scheduling data, incorrect scheduling data, material availability date, perform backorder processing, requested delivery date, main items, distribution document, oltp system, program termination
Related Notes : 
       
| 539643 | Confirmed schedule line is not created in the OLTP System | 
| 535213 | No update in OLTP sales document | 
| 375193 | Backorder processing: Composite SAP note on posting |