I haven't seen that issue. We experience really cold winters here and have had my F56 in the parking lot in -30C temperatures without any issues starting the car.Had my F55 since november 2014 going well, loving the 1.5 petrol - fuel economy, performance all good.
Yesterday was a particularly cold evening and I saw a new warning message for the 1st time
battery was discharging
note in visual boast radio advised I needed to go on a prolonged drive and if this problem came back to visit a dealer.
I am not sure why this message came up but this morning it was not there.
Has anyone else had a similar event with their car and if so what did you do / find out.
please let me know
Most probably a battery issue, best take it to the dealer.