Field help (TNSFLG3) 

Specifies the DO type. If it is triggered as "Pending transfer", this means that the DO has been shipped, via an "inter-site" round, to another site. On this site, the final shipment to the ship-to customer has no taken place yet. Once said final shipment has been confirmed, the DO will move to status 9-Shipped/Closed on its original site.