It's most likely related to the fuel pump/sensor/control unit issue. There have been increasing number of occurences reported in this forum and Bimmerfest forum.
http://www.bimmerfest.com/forums/sho...d.php?t=596310
Most likely it's not the fuel pump, but it's the fuel level sensor control unit.
I have the same car as you but have not yet experience this issue ... hopefully, I won't.
btw, BMW Toronto ususally does a pretty job in sorting out this problem. If no luck, try Parkview (sister dealership of BMW Toronto).