The Crew-10 astronauts must arrive at the International Space Station before Williams and Wilmore, who are currently assigned to the Crew-9 mission, can complete their rotation on the orbiting laboratory and head back to Earth.

SpaceX and NASA under pressure to get a pair of Boeing Starliner astronauts home sooner than later announced Tuesday they have shifted plans for the next mission to the International Space Station.

NASA on Tuesday swapped out the astronaut capsule it plans to use for an upcoming routine flight to the International Space Station, a scheduling move that will allow a slightly earlier return for two Starliner astronauts who have been on the station far longer than expected.

The return of two astronauts, Butch Wilmore and Suni Williams, who flew to the International Space Station on Boeing's faulty Starliner capsule last summer, has hinged on the arrival of the Crew-10's four-person crew in order to keep the station's American contingent staffed at normal levels.