Updates details of a shipment plan identified by the shipmentPlanId. This is a partial update, meaning that only the provided fields will be updated. If ruleIds field is specified, it will replace the existing rules currently associated with the shipment plan.

Note: segments cannot be edited through this API. Changing the order of the segments in a plan would cause shipments created from earlier versions of the plan diverge from a shipment instantiated from the new plan with different segment structure. Individual segments can still be updated via the shipments/v4/plans/{shipmentPlanId}/{segmentPlanId} endpoint.