Tesla CEO Elon Musk on Monday appeared to confirm a report that the company’s much-ballyhooed event to unveil a robotaxi will be delayed beyond its scheduled Aug. 8 date.

Musk didn’t give a new date for the event, but in a posting on X, the social media site he owns, he wrote that he requested a design change to the front of the vehicle.

“The extra time allows us to show off a few other things,” he wrote.

A message was left Monday seeking comment from Tesla.

Bloomberg News reported on Thursday that the robotaxi event would be delayed until October due to changes sought by Musk. That sent Tesla shares down 8% for the day. But they have since rallied and were up nearly 3% in Monday afternoon trading.

Tesla shares had been down more than 40% earlier in the year, but are up more than 80% since hitting a 52-week low in April.

For many years Musk has said Tesla’s “Full Self Driving” system will allow a fleet of robotaxis to generate income for the company and Tesla owners, making use of the electric vehicles when they would have been parked. Musk has been touting self-driving vehicles as a growth catalyst for Tesla since “Full Self Driving” hardware went on sale late in 2015. The system is being tested on public roads by thousands of owners.

But in investigative documents, the U.S. National Highway Traffic Safety Administration said it found 75 crashes and one death involving “Full Self Driving.” It’s not clear whether the system was at fault.

Tesla, which is based in Austin, Texas, has said the system cannot drive itself and that human drivers must be ready to intervene at all times.