I got the same message
AS my FP went to old address, called(08/02) to confirm correct address. They did have my correct address on record (hence the million dollar question - why the hell was the notice sent to old address). Also, never called uscis for any status update either. Anyway, finished my second FP on 12th August. LUD changed on 08/24, 08/25 and 08/26 and ....its anybody's guess.
Got the two emails...
---------------Message
On August 24, 2004, we responded to your request for more information concerning your case. If you have not received our response within 30 days from this date, please call customer service at 1-800-375-5283.