span1234,
My RFE was issued on Dec 4 and received by NSC on Dec 19th. My Case was approved on Mar 12th. Further, my case was reassigned to the officer on Jan 21st. It was pending with him for almost 2 months before it was approved.
I have been noticing this trend especially for Dec RFE cases. Check when your RFE was reassigned to the officer and you should get it within 2 months from that date.
Hang on and Good luck!