Driving a Tesla across America is not an easy task, testing not only the range of the Tesla, but also a variety of variables such as road conditions along the way, weather, and even the personal ability of the driver.
In fact, Drive.ai has done this kind of self-driving long-distance journey before, calling it The Drive-a-thon and documenting the thrilling "24-hour drive diary" in detail.
Recently, in response to a question about autopilot, Musk said he would do a cross-continental U.S. autopilot in a 3-6 month time frame. When asked if the "crossover driving feature" would be available to regular Tesla customers, he said "in the future, yes," but didn't comment on when it would be available.
Musk admitted that he "missed the mark" on the goal he set last year, but determined that Tesla "had the ability to complete the cross-continental cross-country program last year." In order to reach this goal, companies need to knock out very much custom code. "This way other Tesla users can also use this feature, but only for specific trans-US routes."