production order doubt

Hi,

My client's requirement is suppose production order is for 50 quantities. Production has not yet started say for example.due to capacity bottle neck or whatever reason, client decides to produce 30 quantities in house and rest 20 quantity by procurement from outside.How to do this is SAP?

Next doubt:say production order of 50 quantities has begun. 10 quantities have been produced.Now client says they want to do inhouse production for next 25 and external procurement for rest 15 quantities.

Please help how to do this?

Regards.