Have you tried emailing the center? My case was audited (no reason given) and after waiting 90 days my lawyer suggested that my employer email the processing center. We received a response several weeks later saying they apologize for the delay and that notice will be forthcoming shortly.
Unfortunately I got a denial two weeks ago - they said the reason was that the documentation did not have two original signatures!! My lawyer states he has copies which show the signatures so I'm not sure what they are on about! He has sent in a "request for reconsideration" last week and I have not heard back from them yet.
Has this happened to anyone else?