With the new B2B site the option is there for a customer/office to place more than one DTP order at a time. This is very convenient but in the US market we offer more than one method of shipping at checkout for DTP orders and current set up is all orders will ship the same method.
We are working with walkme to have a pop up to inform customers of this but for the overall user experience they should be able to choose the MOT for each order.