Their initial "hand over" is to employees, not real customers, so it is really just internal testing and does not indicate anything about when actual deliveries will begin.
Hitting delivery deadlines is actually worse than missing them if you are hitting them by pushing an unfinished product which is losing tons of money per unit due to inefficient production processes and creating huge future liabilities for warranty repairs, recalls, and negligence lawsuits if someone gets injured by a defect.
There is a reason why Goldman is revising their price target down on this news and their target is half the current stock price.