During a press conference today, NASA representatives confirmed they have a contingency plan to bring astronauts Barry Wilmore and Sunita Williams home from the International Space Station (ISS) early next year. If they’re unable to leave sooner aboard the Boeing Starliner spacecraft that brought them there, the backup plan would rely on SpaceX’s Crew-9 mission, which has had its launch delayed while officials figure out what to do next.

After a successful crewed launch of the Boeing Starliner on June 5th (following several delays), the two astronauts were originally supposed to spend about a week aboard the ISS before parachuting back to Earth. But the Starliner experienced thruster failures and helium leaks while docking with the ISS, plus additional delays that have left the astronauts stuck in orbit for over two months while Boeing and NASA try to determine if the vehicle is still safe to use.

The June crewed test flight was originally scheduled to take place seven years ago, and Boeing’s Starliner program has experienced significant delays and cost overruns. If SpaceX ends up having to bring the two astronauts back to Earth, it’s just one more misstep for Boeing in a year that included a door plug exploding out from one of its planes during a flight and pleading guilty to a criminal fraud charge.

Tests conducted at NASA’s White Sands Test Facility pointed to deformed Teflon seals being a potential cause of the Starliner’s thrusters failing, but the agency isn’t expected to make a final decision on whether or not Williams and Wilmore will return using Boeing’s spacecraft until mid-August.

Using Starliner is still NASA’s preferred solution, according to officials, but the backup plan would see SpaceX send just two astronauts to the ISS aboard a late September Crew-9 launch, leaving two spots available for Williams and Wilmore to use to return in February of next year. Should that happen, Boeing will reconfigure the Starliner craft so that it can return to Earth uncrewed ahead of the SpaceX Crew-9 launch.