It appears that the last hardware to go in is the electric utility's transformer. Once that's in, as a rule Tesla's contractor finishes up speedily, and the final city/county inspection is normally easy enough.
I've been told that rural or small utility companies can't afford to keep big, expensive and rarely-asked-for transformers ready to go in a warehouse somewhere, so they place an order for one from a manufacturer like General Electric only when one is needed — but regrettably that can take weeks or even months.
Anybody happen to notice if the transformer is in yet, or is it just an empty pad?