September 21, 2021: -Electric vehicle maker Tesla is poised to expand its controversial FSD Beta program with a long-awaited download button that allows customers to get new, unfinished versions of the company’s driver assistance software to test on public roads even though that software hasn’t been debugged yet.

Tesla CEO Elon Musk, a previous version of FSD Beta software “not great,” cautioned Friday evening that FSD Beta seems so good it can give drivers a false sense of security that they don’t need to pay attention to driving. At the same time, FSD Beta is engaged, even though they do have to remain attentive and at the wheel.

Tesla markets its driver assistance systems in a standard package known as Autopilot. According to its user manuals website, a premium package is known as FSD, short for Full Self-Driving in the U.S. Neither of these systems makes Tesla’s cars autonomous.

Musk has promised his fans an FSD Beta button for six months. On March 9, 2021, he wrote, “Build 8.3 of FSD should be done QA testing by the end of next week, so that’s roughly when the download button should show up.”

The CEO also revealed Thursday that Tesla would require owners who use the forthcoming Beta button to prove they are good drivers before getting access to their FSD Beta download.

Musk writes that the “Beta button will request permission to assess driving behavior using Tesla insurance calculator. If driving behavior is good for seven days, beta access will be granted.”

Tesla board member, Hiromichi Mizuno, shared Musk’s announcement and touted the company’s approach, writing on Friday, “You should be a good driver not to drive, which may become a new norm.”

“Ironically, yes at this time. FSD beta system, at times, can seem so good that vigilance isn’t necessary, but it is. Also, the beta user who isn’t super careful will get booted. Two thousand beta users operate for almost a year with no accidents. Needs to stay that way.”

Musk tweeted contradict facts about the FSD Beta program conveyed in the California Department of Motor Vehicles Autonomous Vehicles Branch memo written in March 2021.

The DMV’s Autonomous Vehicles Branch Chief Miguel Acosta, writing the memo, spoke with Tesla employees on that date, which include associate general counsel Eric Williams and Autopilot software director CJ Moore.

Acosta wrote that they informed him that the FSD Beta program as of March 9, 2021, included 753 Tesla employees and 71 non-employees, less than half of the 2,000 FSD Beta users Musk alluded to in his tweet Friday.

CNBC directly obtained the memo and other correspondence amid Tesla and the California DMV, published earlier by Plain site, a legal transparency website.