I am away on a four week trip and the battery was at 70% when I left. Before leaving I plugged the car in and also lowered the charge level to 50% so I could determine the daily draw of the car when not in use until it reached 50%. I figured it would then keep the battery at 50% until I got back home, but It seems the battery keeps charging to the level it was when I plugged in before leaving (70%). Is this normal behavior? It has now been a week and every time I see the % go down on the Tesla App, it then goes up again to 70%.