The Boeing Starliner crew might not return this year — or on the Boeing Starliner

Boeing’s CST-100 Starliner spacecraft is still stuck in orbit, and it still remains unclear when it or its crew might come back to Earth. NASA representatives provided an update to the craft’s mission Wednesday suggesting that planning for a return trip might stretch from late this summer into late this winter — possibly aboard a vessel from Boeing rival SpaceX.

“Our prime option is to return Butch and Suni on Starliner,” Steve Stich, the manager of NASA’s Commercial Crew Program, said. “However, we have done the requisite planning to make sure we have other options open, and so we have been working with SpaceX to ensure that they’re ready to respond.”

Leaks from the helium tanks that control the Starliner’s thrusters is the key problem that delayed the ship’s launch and has kept it stuck to its docking port at the International Space Station since June. Boeing and NASA said last month that testing of the thrusters was done and that they were going over the data to prepare for a return mission. But after going over that data scientists found some problems with the helium tank seals that gave them a bit of pause.

Now, NASA thinks it makes increasingly more sense to explore sending Sunita Williams and Butch Wilmore home aboard a SpaceX Dragon ship that’s launching for the ISS next month — and returning in February.