It didn't take long to plan the departure. After Khan refused the additional tests, the Thilku couldn't wait to kick him out of the planet, so the authorizations for ships and teleports arrived in a matter of hours.
Khan also didn't delay his stay. As soon as soldiers knocked on his door, he left the room and followed the escort to start the inevitable return.
The abrupt departure didn't give Khan time to study the Empire's records, but he preferred it that way. He needed additional resources and machines to make sense of the new information in his possession. Also, he had something else in mind and couldn't handle it while inside the Empire's territory.
The trips between the two domains were always long. By the time Khan returned to the Global Army's territory, the afternoon had turned into morning, and the voyage had yet to end.