After cleaning up any traces he might have left in Japan, Yan Fei returned to the Drone and activated it for a stealth flight, hugging the ground as he made his way back out to the open sea. His mission in Japan had been completed beyond expectations, but various unexpected events and emergencies kept him in the country for over a week. To maintain secrecy, he hadn't made contact with Lu Pingping back in China during this time, and had no idea how the domestic situation at the Company had developed; he was starting to miss his company and friends back home.
So as soon as he completed his mission, Yan Fei decided to return to China immediately. Originally, the safest choice would have been to let the Drone make its way underwater back to China at a slow pace. However, Yan Fei found the underwater pace of the Drone too slow and chose to have it fly at a low altitude near the sea surface to quickly advance toward China.