Enmanuel:

so wait, did I miss something or are the dealers installing the new engines? 

I would't like that at all.

Who else would do that that?  No way they can ship the cars back to germany for a simple engine swap which takes a few hours.  Trust me. The shipping would be far more damaging than an engine swap at the dealer.  Just don't want to be the first one.  After a couple the techs will be doing them in their sleep.  Not complicated at all.