Remember, the GOM gives a mileage modified by your driving history. When the weather turns cold (LOL, I am in Oregon and here 35F is "cold"), if I start out with a "cold start" in my car, I find the miles literally melt away for about 25 minutes as the cabin and battery get warmed up. When I charge, for my charging setup I use the Audi charger and set up charging timers via the App/MMI, so I can't say what happens if you are using a different charger. Along the lines suggested by "polyphonic", I set up a timer and enable "auxiliary" conditioning. The Audi timer is based on the Departure time you give it. When "auxiliary" is enabled, the car pulls current from the wall to heat the cabin and warm the battery. (There is some question as to if this "auxiliary" system is available if you did not get the Cold Weather Package.) The whole charging/conditioning cycle is timed by the car to start so that it is completed by the Departure time you have set. The conditioning can run off the wall for an additional 30 minutes or so (from the wall) after charging has been completed to keep the cabin at the desired temperature. When I use a timer in cold weather, I find that this issue of "melting miles" phenomenon last for less than 10 minutes (as oppsed to 25). You might find that improves your GOM readings. I find this preconditioning may spare me 20 miles or more, as estimated by the GOM. I have not really tested it yet, but I imagine making judicious use of seat heaters, as opposed to relying on the cabin air, might improve GOM, as well. It seems to improve my GOM currently, when I use the seat A/C to offset cabin air.