Tracing assemblies for items on backorder

Currently the backorder process means that once the material with that SKU becomes available, the order will be assembled on the next fullfilment. As such, we are not able to easily trace which sales order the assembly relates to, as it only references the order which triggered the process and not that which had the backorder. It is important that our client has full control of the movement of inventory, and so should be able to manually schedule fulfillment of the backorder as opposed to it happening automatically when the next sale is processed. It is important that the flow of inventory in Dear reflects what is actually happening in the warehouses.