Reservation on the basis of Requested ship date first then quantity

Summary:

I come across with one requirement which is related to orchestration process.

Actually we are facing some challenges in reservation in orchestration process.

Suppose I have created one sales order with one lines and require 200 quantity against that sales order.

But available qty's is only 100 qty's. Until we don't have stock of 200 SO won't proceed.

After some days, we have created one more sales order with same Item but quantity require 50 against this order.

So we have available 150 qty's so basis on that It is passed reservation process now Available stock got declined from 150 to 100. So for the first order It will take more days to fulfill..