H1B extension 3yrs based on i140 before completing 6 years on present H1B

[Satya007]

Question: The H1B is expiring in Mid 2017 and i140(EB-2) is expected to be Approved by September 2016. Can I file for an extension till 2020 in September 2016(My Present Visa will expire in Feb 2016 and can get extension on that till Mid 2016 also, but I want to extend it to 3 + years after September). Thanks!