Improved SOP Despatched column for linked orders

The Despatched SOP List View Column is useful as it allows you to quickly filter and review sales orders with their associated despatch status, i.e. part, full. However this doesn't apply to Sales orders that has item lines with linked purchase orders. For example, a Sales Order has two lines: a carriage line, and also an item line which is linked to a Purchase Order (direct to customer fulfilment method). As soon as the Order has been created the SOP List Column Ready for invoice will state Yes because the carriage line can be invoiced. But the Despatched column cant be used to filter these orders that are truly ready to be invoiced because the Despatched column doesn't consider the linked item line. Ideally the Despatched SOP List column will consider all three fulfilment methods, and truly reflect whether it is fully or part despatched.