Tesla told a California regulator that it may not achieve full self-driving technology by the end of this year, a memo by the California Department of Motor Vehicles (DMV) has shown.

During an earnings conference call in January, Tesla CEO Elon Musk said he was “highly confident the car will be able to drive itself with reliability in excess of human this year.”

Tesla Inc has also rolled out what it calls a “beta” version of its “full self-driving” (FSD) program to a limited number of customers and employees since October, and Musk has promoted the capability on Twitter.

The California DMV said in a memo about its March 9 conference call with Tesla representatives, including autopilot engineer CJ Moore, that “Elon’s tweet does not match engineering reality per CJ. Tesla is at Level 2 currently.” Level 2 technology refers to a semi-automated driving system, which requires supervision by a human driver.

The memo was released by legal transparency group PlainSite, which obtained it under the Freedom of Information Act (FOIA).

“Tesla indicated that Elon is extrapolating on the rates of improvement when speaking about L5 capabilities. Tesla couldn’t say if the rate of improvement would make it to L5 by end of calendar year,” the memo stated as it referred to level 5 full autonomous technology.