The problem can't be seen anywhere now, but will become visible if new additional properties will be stored as part of shipping info during In-Commerce customization.
In-Commerce allows for Administrator to edit orders, submitted on the Front-End. In particular the "Shipping tab" allows to change both shipping address and shipping type (FedEx, UPS, etc.).
In cases, when shipping price (acquired from shipping quote engine, e.g. FedEx or UPS) is different based on time, when price query is made (e.g. FedEx returns $12.90 on Monday, but $12.00 on Friday), then shipping type selected in the order can be be missing when Administrator opens that order.
When editing an order in the Admin Console always retrieve selected shipping type information from that order.