If you would like to override the reference label fields for certain carriers, you can choose several options in Map Label Fields.
Click the Settings tab.
Under “Admin Settings” select “Map Label Fields”.
Check the "Override Order Fields" if you would like to override any information added on the ship or batch tab.
Select the carrier from the drop-down you would like to apply the changes to.
After selecting the carrier, it will give the options you can map such as Reference, PO Number, or Department.
Choose the option from the drop-down to use as the reference.
Select "Save Changes" when done.
Note: The Map Label Fields will only override the information that is sent with the order data from the integration.
For example, if you have a Woocommerce integration, with an order that contains items that do not have an SKU assigned to them, and you have the Map Label Field for Reference 1 set to override with one of the SKU options as shown in the picture below:
You will see that after selecting the order, service, and package type it will leave that field (Reference1) blank.