By Sheri Walsh 1 of 2 | NASA Astronauts Suni Williams (L) and Butch Wilmore pose for family members after walking out from the Operations and Checkout Building at the Kennedy Space Center, Florida on June 5. The astronauts were stranded at the International Space Station after Boeing's Starliner suffered helium leaks and thruster issues, forcing the spacecraft to return to Earth empty. NASA announced Tuesday it could be late March before Williams and Wilmore head home. File Photo by Joe Marino/UPI | License Photo Dec. 17 (UPI) -- Two Boeing Starliner astronauts, stranded at the International Space Station in June after what was supposed to be a weeklong test flight, are facing a new delay in their return trip to Earth, NASA revealed Tuesday. Suni Williams and Butch Wilmore had been scheduled to return on a SpaceX Dragon flight in February, after they were forced to abandon Starliner due to helium leaks and thruster issues. The pair will now return to Earth no earlier than late March, 10 months after they originally launched, as they wait for their replacements to arrive at the ISS. Advertisement "NASA's SpaceX Crew-10 now is targeting no earlier than late March 2025 to launch four crew members to the space station," NASA wrote Tuesday in a post on X. "The change gives NASA and SpaceX time to complete processing on a new Dragon spacecraft for the mission, set to arrive in early January." Advertisement NASA's SpaceX #Crew10 now is targeting no earlier than late March 2025 to launch four crew members to @Space_Station. The change gives NASA and SpaceX time to complete processing on a new Dragon spacecraft for the mission, set to arrive in early January: https://t.co/3y1zvsyGMr pic.twitter.com/wJxfV89SAR— NASA Commercial Crew (@Commercial_Crew) December 17, 2024 "Fabrication, assembly, testing and final integration of a new spacecraft is a painstaking endeavor that requires great attention to detail," said Steve Stich, manager of NASA's Commercial Crew Program. "We appreciate the hard work by the SpaceX team to expand the Dragon fleet in support of our missions and the flexibility of the station program and expedition crews as we work together to complete the new capsule's readiness for flight," Stich added Tuesday. Wilmore and Williams arrived at the ISS on June 6, on what was the first crewed test flight of Boeing's Starliner capsule. The mission was supposed to be the final step before NASA certified Boeing to fly crews to and from the space station, but faulty thrusters stranded the pair. Starliner returned to Earth uncrewed in September and NASA sent only two astronauts, instead of four, on its SpaceX Crew-9 mission to leave room for Wilmore and Williams when they return next year. Advertisement The astronauts are waiting for SpaceX Crew-10 to replace them on ISS. NASA prefers to have overlapping crews at the space station for smoother transitions, according to officials. The agency's SpaceX Crew-9 mission with astronauts Nick Hague, as well as Williams and Wilmore, and Roscosmos cosmonaut Aleksandr Gorbunov will return to Earth following the arrival of Crew-10. The handover period allows astronauts to exchange information about ongoing science experiments and maintenance projects. Two resupply flights in November brought the crew more food, water, clothing and oxygen, as well as items to celebrate the holidays. SpaceX has been transporting astronauts to and from the ISS since 2020. Plans for Boeing's Starliner to become a significant part of NASA's commercial payload program will continue, according to the agency, despite technical problems that made the "risk to the crew higher than they wanted." Both the SpaceX Crew Dragon capsule and Boeing's Starliner are slated to become NASA's vehicles to shuttle astronauts to and from the space station and its eventual replacement, while supporting future missions to the moon and Mars.