I've noticed that my rated range at 90% has been slowly dropping moving from autumn into winter. I've speculated that it is due to the temperature of the battery when it completes the charge. I believe I've now proved it. My charge level has not moved from 90%. This month I'm down to 219-220 miles on a 90% charge with range mode disabled. To raise the heat of the battery, I turned on "Max Battery Power" then plugged in my car and told the car to charge immediately instead of waiting for my scheduled charge. The result was 224 miles of rated range at 90% with range mode disabled. I believe this proves that ambient temperature will cause the rated ranged to lower during cold seasons, and increase again as temperatures warm. I'd like to see others in cold climates repeat this experiment and post their results. In case it matters to anyone, my P85D has about 27k miles on it.