The chances of getting a software quicker by being connected to Wi-Fi seems like utter smoke out your a*$ from Tesla. We have a 2017 Model S and a 2017 Model X . Both have rock solid Wi-Fi connections and are always connected as soon as we park in the garage. We have never not even once received software updates even on the same day. Most current example my car, S100D, received 2018.39.6 early Saturday morning around 3:00am. My wife's Model X parked right next to it and on the same Wi-Fi network has yet to receive .39 and that car is on the network much more than my car.
The statement by Tesla about "connected to Wi-Fi" is true ONLY if your car has already been magically selected for the update. The rest is purely and totally in Teslas' hands and their magical black 8 ball.
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