Which event would NOT require the Commanding Officer to order the ship to man the rails?

Manning the rails is a ceremonial practice in which crew members stand at attention on the ship's rails or decks, signaling the ship's approach to significant events such as entering or leaving ports, especially in a formal setting.

Given this context, when a ship leaves the shipyards after an extensive maintenance period, such as 120 days, it is not traditionally a ceremonial event that warrants manning the rails. This situation typically involves more practical concerns, including ensuring the ship is in proper working order and preparing for operations rather than presenting a ceremonial display. In contrast, ceremonies are more commonly held during the arrival at a foreign port, transiting through a canal, or participating in a military exercise, where manning the rails serves to show professionalism and respect to the local populace or other military forces.

Thus, the transition out of shipyards does not align with the ceremonial nature of manning the rails, making it the event that would not require the Commanding Officer to issue such an order.