I went through quite a roller coaster ride. Initially they said the file is lost, asked me to submit a duplicate. Then I followed up with a congressman, they said 140 is in my file. After lot more inquiries from my congressman they adjudicated both my 140 and 485 together. I never heard Extended review ever, but typically that means they are investigating your employer could be either DOL or USCIS audit, hence until that audit clears they may not adjudicate your 140.