I'm not necessarily saying "TSLA Will definitely run out of money in 3-quarters". I'm saying "TSLA is currently, on a linear-approximation track to run out of money in 3-quarters".
Obviously, the Model 3 rampup will improve profitability. But the Model 3 Ramp-up also requires more resources (more humans in the assembly line. More robots in the assembly line. etc. etc.). So that still requires money.
A linear approximation is basically a quick-but-shitty-approximation. Its really easy to calculate and full of flaws, but full of flaws in a way that almost everyone can immediately understand.
Exponential approximations (ie: Musk's approach) might be more realistic... since production lines can exponentially grow to some degree. But if you are off by even a little bit, then you end up being ... oh I dunno... 8-months to 10 months late with your 5000-cars per-week estimate.
It is obvious to anybody looking at the balance sheets of the company that TSLA will need to raise capital soon. Either late 2018 or maybe early 2019. A company with $3 Billion cash that's losing $1-billion per quarter will need more money. That's just the facts.
Musk is going to be either relying upon institutional investors / the stock market in general for another round of equity offerings, or relying upon banks for a loan. In either case, it seems like Musk just bit the hand that feeds his company money.
Another 300,000 reservations at $1000 per is probably not going to happen. There are fewer and fewer ways for TSLA to raise tons of money.