I have about 500 miles on my 2016 M3W. I have been breaking it I slowly since the winter.
but I never had this noise until yesterday and it started soon after that initial clanking when I "banged" it into 2nd gear under full acceleration.
I could be flippant here and suggest that the two quotes may have had a bearing on the noises..!!
It's under warranty, get it to a dealer and let them look. If it means a breakdown truck, so be it.
