I'm not a GAAP Accounting whiz, but you need to book labor related expenses on the months they occur which much be a large portion of Tesla's expenses. You then can reach profitability by recognizing all sales in one month whereas if you spread out your sales over a few months you would not have. This kind of cookie jarring is borderline illegal but I suspect happens all the time in corporations because it is brilliant press and satisfies your investors.

Also, I'd hope that most of their revenue is directly attributable to selling cars. What they might have is an amount of each sale hitting deferred revenue and recognize it over the length of the warranty (similar to iPod).

Edit: Apologies for finance nerd rage, I'd love for someone to clarify what can and can't be done under GAAP though.