My case (I140/485) was filed to VSC last September, and then was transfered to NSC this May. I called USCIS a couple of times and spoke with several superisors. Unfortunatelly I was told that NSC won't touch such transfered cases until 180 days after transfer. That means we have to wait for at least 9months+6months=15months. One of the USCIS supervisors suggested me to file the complaint to:
Director, Office of Internal Audit
425 I Street, NW
Room 3260
Washington, DC 20536
If you are one of the victoms, and if you don't want your case sleeps in NSC for another 6+ months, I would suggest you file your complaint to above address.