Two astronauts relinquished their seats on a four-person spacecraft so that their colleagues could return to Earth from the ISS, where they’ve been stuck since June.

What should have been a fairly quick trip for Suni and Butch has turned into a months-long ordeal. While SpaceX’s mission arrived at the ISS this weekend, its return trip bringing the stranded astronauts back to Earth won’t take place until February 2025.

NASA astronaut Nick Hague and Roscosmos cosmonaut Aleksandr Gorbunov boarded the ISS shortly after the Dragon capsule docked at the station at 2130 GMT, NASA said in a post on X. The SpaceX Crew-9 mission was supposed to transport four astronauts to the ISS until two empty seats had to be opened up for Wilmore and Williams after the Boeing Starliner capsule they arrived on in June was deemed unfit to return them to Earth.

SpaceX launched the rescue mission on Saturday with a downsized crew of two astronauts and two empty seats reserved for Butch Wilmore and Suni Williams, who will return next year. The Dragon capsule docked in darkness high over Botswana as the two craft soared 260 miles (420 kilometers) above Earth.

SpaceX is set to launch two crew members to the space station in a capsule that will eventually bring home the NASA astronauts who flew on Boeing’s Starliner spacecraft.

The craft will return Butch Wilmore and Suni Williams - stranded since June - to Earth.

The SpaceX capsule will eventually bring home Butch Wilmore and Suni Williams, the NASA astronauts who piloted the Boeing Starliner test flight.