Topline SpaceX canceled a ship launch Wednesday that is part of a mission to bring back two astronauts who have been on the International Space Station for nine months after the Boeing spacecraft they arrived in was deemed unsafe over helium leaks and thruster issues.

The replacements for NASA’s two stuck astronauts launched to the International Space Station on Friday night, paving the way for the pair’s return after nine long months. Butch Wilmore and Suni Williams need SpaceX to get this relief team to the space station before they can check out.