At what average speed are you seeing 294 miles. I can barely get 260 miles at 15 mph average speed and this is driving very conservatively.i get 235 miles on an 80% charge. On a full charge that I only do for a long trip I get 294 miles. This is in warm months. In Feb in Central NH I was getting 235 on a full charge. 210-220 on a 80%. But the car was new and learning my driving .
edit
this was last night 76 degrees driving around town.
I guess if I do the same with 296/77 it comes to 3.8 so half mile different so maybe sitting at stop lights could be the difference, but since you get this on long distance drives I’m assuming you average MPH is going to be quite a bit higher then 15 mph.