"Document Option" for the return shipping labels

"Document Option" (Label Messages) for the return shipping labels

I need to add messages to the reference fields on the UPS return label, like the options in the outbound UPS label.

It would be useful us to add the RMA # we input on the UPS return label so that it can be present on our reports from UPS

This would be highly useful to our workflow and it appears as others believe this would be beneficial as well: 

https://community.shipstation.com/t5/Orders-Shipment-Management/Reference-fields-in-UPS-return-labels/idi-p/6615