Teslas are about to get a huge upgrade by Valentina Zarya @FortuneMagazine July 31, 2015, 4:32 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons Tesla CEO Elon Musk said in an early morning tweet Friday that his electric car company is “almost ready to release highway autosteer and parallel autopark software update.” This is not the first time that Musk has alluded to a self-driving Tesla. In a call with reporters back in March, Musk said: “We’re now almost able to travel all the way from San Francisco to Seattle without the driver touching any controls at all.” It is unclear what Musk means by the “almost” in his tweet. Are self-driving cars going to be on the market a week from now? A month? A year? Musk’s following tweet, which details a few of the remaining issues, seems to imply that it will happen sooner rather than later: “Final corner case is dealing with low contrast lane markings (faded white on grey concrete) while driving into the sun at dusk,” he said. Whenever it happens, the update will arrive as part of the Model S Version 7, and will have a “[minimum] caliber of starting quality,” Musk said Friday in yet another tweet. But it will only get better from there, he promised: “The car will learn over time.” Sign up for Data Sheet, Fortune’s daily morning newsletter about the business of technology.