Less regen maybe? It's more about what's left on the battery than what's been used, so if you're not braking as much that's one possibility.
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The "kWh Used" number is an estimate, not a meter reading, because it’s actually a net calculation = grid power consumed less regen put back in. The system accounts for variation in the amount of regen during a trip by subtracting it from the kWh Used number on the display (you can sometimes see the number get smaller because of regen as you drive down a long hill), so you, in effect, get to use it again. Since the amount of grid power is consistent from full charge to full charge, the more hills you drove down and the more braking you did, the higher the total power consumed would be if the "kWh used" number was the sum of the grid power used and the regen you got during the trip instead of the difference. By eliminating regen count from the total trip kWh Used, you get a fairly consistent kWh Used number for every fully depleted battery use.
Of course, driving down the road uses the battery and lowers the state of charge, and getting regen by driving down a hill then raises it again. Once the Battery State Estimate algorithm has determined the SOC has dropped to the minimum allowable point, the car switches to ICE and the battery is considered "fully depleted." Why the computer determines it’s time to switch on the ICE one day when you’ve used 14 kWh of your Gen 2's power, and another day when you’ve only used 13.7, is for others to explain...