Amidst the hubbub over Tesla CEO Elon Musk’s somewhat abrupt decision to keep the company public, he also took to Twitter to share an update on the Tesla Semi, the company’s highly anticipated electric powered truck. According to a tweet from Musk, the Semi can now be “driven across the country” without support vehicles.

The update came in response to news coverage of a recent prototype spotting that was first covered by Elektrek. This latest spotting appeared to be from employees of the shipping giant J.B. Hunt Transporting Services, who posted pictures of the Semi onto Instagram.

In response to Elektrek’s coverage of the social media posts, Musk added a few new details about how the Tesla Semi’s rollout is progressing, and implied in a tweet that the Semi is now capable of driving cross country without the use of support vehicles.

“What’s cool is that it was driven across the country alone (no escort or any accompanying vehicles), using the existing Tesla Supercharger network and an extension cord,” Musk’s first reply reads. “The extension cord was 1000 miles long, but still.”

When Will the Tesla Semi Hit Roads?

J.B. Hunt was one of the first companies to announce that it had placed a pre-order for the Tesla Semi shortly after the Semi’s first unveiling last year. It’s a giant in the industry, with a market cap of roughly $12 billion and has captured a little more than a quarter of the market for intermodal shipping, according to a 2014 company presentation.

The Tesla Semi isn’t expected to enter production until 2019, and so its recent spotting at J.B. Hunt’s facilities in Arkansas seems like it’s meant to give the impression that things are going ahead of schedule.

The obvious caveat on Musk’s statement was his somewhat tongue in cheek reference to the fact that the Semi still relies in part on a 1,000 foot extension cord in order to travel long distances. As Elektrek’s Fred Lampbert noted, actually refers to a network of cords used to make up the gaps left by Tesla’s regular charging network.

Tesla Semis will eventually run on their own network of “Megachargers” with greater capabilities than the Supercharger network that’s supposed to run Tesla’s cars. When it hits the roads, the Semi is expected to consume less than 2 kWh per mile in energy, with a range of 500 miles for the $180,000 model, though Musk has hinted he expects to beat the initial specs presented at its first unveiling.

You can check out some footage of an early prototypes cruising in California in the video below, taken back in June.