Due to scheduling delays, one of SpaceX’s customers has decided to go with a different rocket. British satellite operator Inmarsat announced today that it will launch one of its satellites on a European Ariane 5 rocket, instead of on one of SpaceX’s vehicles like it had originally planned. On short notice, Inmarsat was able to secure a mid-2017 launch for the spacecraft — a communication satellite for the European Aviation Network (EAN).

“We are delighted with [the] flexibility that Arianespace has shown.”

“We are delighted with [the] flexibility that Arianespace has shown in being able to provide a launch slot that enables us to place our European Aviation Network S-band satellite in orbit by mid-2017,” Michele Franci, CTO of Inmarsat, said in a statement.

The news doesn’t come as too much of a surprise, as time has been running out to get this satellite operating in orbit. The EAN satellite needed to launch before December in order to meet a regulatory deadline put in place by the European Commission, according to Space News. But in August, Inmarsat said it was certain it would miss this deadline, as SpaceX had a stacked schedule of Falcon 9 launches. A launch on SpaceX’s Falcon Heavy — a more powerful variant of the Falcon 9 — wouldn’t have been able to happen until the first quarter of 2017, an Inmarsat spokesperson said at the time. Launching on the Falcon 9 also would have had to wait until later in 2017.

The Falcon Heavy has yet to make its maiden flight, though. SpaceX had planned to fly it for the first time before the end of this year. Then on September 1st, one of SpaceX’s rockets exploded on a Florida launchpad, forcing the company to put all of its launches on hold as it investigated the accident. Citing these launch delays, Inmarsat CEO Rupert Pearce said in November his company was “actively look at alternatives” for the launch of the EAN satellite, according to The Wall Street Journal.

SpaceX announced that the return-to-flight mission will slip to January

CEO Elon Musk claims that SpaceX has since figured out the cause of the explosion, and the company had originally aimed to launch again on December 16th. But yesterday, SpaceX announced that the return-to-flight mission will slip to January and the accident investigation has yet to be finalized.

"We're continuing to make progress with the investigation into our Sept. 1 anomaly and we are working to safely and reliably return to flight in early January,” SpaceX said in a statement to The Verge. “Inmarsat is a long-time partner, and we wish them well with their upcoming mission."

Inmarsat isn’t totally abandoning SpaceX. The company still plans to launch its Inmarsat-5 F4 satellite on a Falcon 9 in the first half of 2017. In a statement, Inmarsat said it is “looking forward to continuing to work with SpaceX going forward.”

Update December 8th, 2:00PM ET: This article was updated to include a statement from SpaceX.