This is the same M differential fluid used in the previous M vehicles:
http://www.ecstuning.com/ES197413/
http://www.rmeuropean.com/Part-Numbe..._E095124A.aspx
The twin turbo f10 is mentioned in that list above (second link). Given the large amount of users however over the 1200 mile limit, this doesn't seem like a serious concern. Situation will be rectified if needed in future oil changes (they should include a differential oil change free of charge if this is an issue).