The FAA’s previous target date was March 28. The FAA noted that completing the environmental review does not guarantee a vehicle operator license will be issued, which must also meet FAA safety, risk and financial responsibility requirements.

Earlier, when asked what he knew about the status of the FAA review, Musk said, "We don't have a ton of insight into where things stand with the FAA," but added: "We have gotten sort of a rough indication there may be an approval in March. But that's all we know."

Even in a "worst-case" scenario, in which a full EIS were required or legal wrangling over the issue threatened to drag on, Musk said SpaceX has a fall-back plan. The company would shift its entire Starship program to the Kennedy Space Center in Cape Canaveral, Florida, where SpaceX already has received the environmental approval it needs, Musk said.

Such a move would cause a setback of six to eight months, he added.

In any case, SpaceX is still shooting for a 2023 launch of what it calls the world's first private lunar mission, flying Japanese entrepreneur Yusaku Maezawa and a dozen artists aboard a Starship to loop around the moon and return to Earth.