Inside of Dear Systems there are 2 options when doing a split shipment or back order being
- Generate a new order with the back ordered items on it
- Turn the order into an 'Advanced' multi shipment order
As at April 2020 The Order Exchange only supports the generation of a new order for the back ordered items. The reason for this is due to a limitation of Dear Systems API (version 1) where the 'Advanced' orders are not able to be returned.
Please use the simple sale technique when doing back orders.