Track their experiment on their twitter feed, which includes a lawyer sealing the charge port to ensure integrity, and the moment they passed the previous record.
Now before anyone goes off on a rant about the fact that they were driving at a unbearably low speed of only 40 kph (around 25 mph), this is not about inflating range reports on the Tesla. The EPA rating stands because it's based on real life usage, and no one is arguing against it.
But this proves a point -- range on EVs are not the same as on gasoline cars.
It seems a driver would have more control over range in an EV than in a gasoline car. Electricity doesn't behave the same way as combustion. If you learn how energy is spent and harvested in an EV, range anxiety is ultimately more troublesome in a gas car. Teslas will even run the diagnostics and give you the option to enter a more efficient range option if needed. (Other car companies need to catch up in this).
And for those just curious about the experiment, here's the youtube clip for your enjoyment!