NASA and SpaceX on Wednesday delayed the launch of a replacement crew of four astronauts to the International Space Station that would have set in motion the long-awaited homecoming of U.S. astronauts Butch Wilmore and Suni Williams.

NASA removed two astronauts from its Crew-9 mission to allow for Williams and Wilmore to join the cohort, and return onboard the SpaceX Dragon − which carries four people at a time. The altered Crew-9 − only Hague and Gorbunov − launched aboard the SpaceX Dragon Freedom in late September.