" Not to pick on Tesla but how can it do all the things it said it was going to do 4 months ago"
It wasn't able to do those things 4 months ago. Tesla announces things like the Model Y to milk its fanbase and get deposits it can use for today's problems and then actually building things like the model Y or whatever else is tomorrow's problem. Elon's biography has a section where Kimbal became concerned in 2008 after Elon blew through all the money, then blew through all the deposit money. Tesla doesn't segregate customer deposits - they're all unsecured creditors.
Tesla raised money the other week and Elon still said shortly after that the $2B raised was "only enough to get through 10 months if Tesla keeps spending as it did in the first quarter of 2019." (https://www.cnbc.com/2019/05/17/elon-musk-calls-for-cost-control-in-memo-to-employees.html)
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