245 means you're not a conservative driver lol, conservative driving I run at 148-155, that means I'm driving between 60-70 mph. Here in Canada currently -10 degrees Celsius, I've been running at 75 mph with heat on and seats on, and I'm running 231, and I drive a MS P85.
My car definitely takes the way I drive into account when factoring in range calculations, and all you need to do to test that theory is change the way you drive. Ex. On an hour to hour half long drive, navigate to where you are going and then drive no more than 60-62 mph, you will find your battery picking up range from they initial calculation. I know that if I drive the speed limit, I can generally pickup 15% more battery compared to the calculation, tried and tested. What you also want to know is that the size of wheel you have makes as difference, I dropped from 21s to 19s and picked up an extra 50 kilometers in range immediately.