This article is from the FAQ, by with numerous contributions by others.
Usually 30-60 days from the date the INS receives the USIA's
recommendation. In my case, the INS received the USIA's
recommendation (dated March 23, 1994) on April 25, 1994. I
received the final waiver letter from the INS (dated June 2, 1994)
yesterday. Therefore, it is approximately 6 weeks processing time.