My experience in columbus, ohio
My timeline:
eb3, priority date June 2002
RFE on 485 for self March 2005, spouse a couple of weeks later.
Replied to RFE beginning of May. Received notice on June 8 that our case was transferred to Cincinnati, Ohio
Made infopass appointment to visit Columbus and was told that Cincinnati was the office that received files from the service center and that Cincinnati would forward the files to Columbus.