In the mrp.production views i would like to show which subcontractor is responsible for the manufacturing order instance.

As a bom can have multiple possible subcontractors, at the stage a mrp.production is created, one subcontractor is already choosen.

Going through the model data in my debugger. I can't find an easy way to get the responsible subcontractor (if any) for the order.

What is the relation ?

I mean, for manufactoring orders a 'group by: subcontractor' sounds like a nice thing, no ?