Yes if you leave the core in a garage with poor or no GPS it will be constantly searching for GPS and drain the battery faster. Plus it’s got a computer and battery and camera heaters. Lots of power drain. Best you can hope for is a couple of days.
Battery drain with the snow blower can vary. Roughly an hour to an hour and a half in dry and powdery snow. Slopes, temperature, load, auger speed, core speed, can all have an impact on battery life. What you are describing sounds consistent and normal to me. I wouldn’t be concerned. I think you’ll be blown away with the mower battery life. I can get 6-7 hours with the M1 and about 4-6 with the M1P (Pro).