[OriginalGriff]

I don't have experience with the EQB yet - I collect it on the 25th - but my B250e (2016) shows the temp is a real killer: even on short journeys on cold winter days, the battery uses 10+ miles range to handle a 6 mile journey, as well as losing range overnight. (This is typical for lithium batteries - you may notice the same effect on your phone.) Using preheat does improve this, but doesn't remove it.
In winter, my range drops by maybe 40% compared to summer usage.