Behaviour of multi-level BOMs

Assuming a two level Bom with two sub-assemblies with everything needed in stock, if in the PO “Use Multi-Level BOM” is not selected then, as I understand, the two sub-assemblies will be drawn from stock and used in the production and not produced from raw-materials (also available in stock).

If “Use Multi-Level BOM” is selected, will any existing sub-assemblies in stock be ignored?

What will happen if one of the two sub-assemblies is not available in stock (in sub-assembly form) but the raw materials to produce the sub-assembly exist in stock?

Is there a way to first use any sub-assemblies in stock as default and if not in stock then expand to also create only the missing sub-assemblies?

Currently erpnext does not behave this way. It does not check stock available or not, assuming is sub-assembly is not available, then it should be created first.


As the “missing” sub-assembly is a subcontracted item, am I corrected in assuming that the Manufacturing order without “multi-level Bom” selected will still raise a MREQ that can raise a Purchase Order from the subcontractor for the “missing” sub-assembly (using the lower level BOM)?