Got very interesting info from the BMW European delivery department
(1-800-932-0831) which pretty much confirms info in this thread....
The tentative launch date for first pick-up is March 1st, which would coincide with how production started 7 years ago. But as mentioned here, its a 2012 F30, so it would appear that the 2013 MY will start later (my guess is in August), but there's no info on what they'll be changing.