submitted in last November, only updated in 8/5/2007, no ref. I have asked about LUD in this forum, Most of people agree that LUD in the weekend is produced by sysetem update. So through my case, LUD is not sysetem update, almostly someone of USCIS do something in your case.
Also my backround is very weak, Ph.D in China, in USA 4 years, no first-author paper in USA. I am so luck that I got approved no ref.
Thanks all.