You can see from my signature that my I140 was approved after 26 months which might be the record approval time for I140. Before that, my attorney initiated a couple of inquiry on I140, no response. I contacted the senator office and was told pending review. Later on my attorney filed another inquiry with immigration attorney association which is a very powerful association per my attorney. Days later, the attorney called me telling me the security review was cleared and my I140 will be adjudiated.
Good luck.