I have a long range X, build date 09/19/19, and for the first time left it parked for a period of 9 days. Looks like it went from range of 275 to 160 miles in that period of time, or about 13 miles per day. I did nothing to prep it for the extended parking, but it looks like I will need to learn the tricks mentioned in this thread, or find a location where it can be plugged in. I know Sentry was on, because it seems logical to me if I am away from the car for an extended period, I would want it turned on! I do not have FSD so no issue of Summon being on. I did check the range about once a day via the Tesla app, and I also have TeslaFi. As mentioned by others it seems like there should be a "long term park" setting. The temperature during the 9 days was about 70 degrees F. Just another learning experience form my first EV!