I should add what others have said in that it's probably unwise to rive so long without a rest. In an ICE vehicle I would always stop for a coffee or comfort break on that journey. I actually didn't stop the last 2 times I did it in my Model 3 but I feel that was more a "because I can" than a sensible route planning choice. As others have mentioned there is god supercharger coverage on that journey so I just would plan a stop. Closer to the end than the beginning for a more efficient charge speed too. Also I'm not sure if it was just a misreading, because the distance is similar, but I took the M6 toll last time rather than the M6 (ruling out a Hilton park top up) and my expected arrival energy shot up by 6%. I assume it was just a blip because both roads are similar in length and time.