My 2012 335i order was placed last march, the 5th. As of May 1 the car was still showing the same thing as the OP so I called my dealer, they basically told me they were over allocating 3 series and that my car was bumped (each dealer has allocations, when they use their allocations they cannot place anymore orders for that car. They can trade an allocation or just take money and wait until one opens up for the dealer).
Sounds like your dealer took your name, money and lied about the production timeline... They know your committed to the car so it's just that things were "delayed"... The car I ordered would have been bumped to a 2013 had waited...
I was ripped but I took a car that was already here, I wish I had dynamic suspension and BMW apps but the 8 sport AT was a good choice that I wouldn't have if I went with my order.
'12 335i Sport Apline White w/black