How to Convert a 3-Leg International Shipment to 2 Legs in OTM Without un/reassigning Shipments?

Has anyone come across a requirement in OTM where an international order is initially planned into 3 legs:

1. Drayage: Sunnyside, WA to Wallula, WA
2. Intermodal (Rail): Wallula, WA to Seattle Port, WA
3. Ocean: Seattle Port, WA to Kobe, Japan

Then, after planning, the user wants to convert it into a 2-leg shipment without unassigning or recreating the shipments:

1. Drayage: Sunnyside, WA to Seattle Port, WA
2. Ocean: Seattle Port, WA to Kobe, Japan

The expectation is to keep the same shipment IDs for leg 1 and leg 2, remove the intermodal leg, and only change the destination of leg 1 from Wallula, WA to Seattle Port, WA.