Is it worth to apply Non premium cap-exemption for stamped, unused, revoked H1B visa expiring in Sept 2017?

Hi ,I have got H1B from Employer A in 2014 and got STAMPED on October 2014 valid till September 2017. But i have not yet traveled on that visa.I joined new employer in Mar 2016.My H1B is revoked by my previous employer in July 2016.

My new employer had filed Cap exemption (NON PREMIUM) in February 2017.It may take till June or July for the response.

If the response is positive,

  1. Do I have to go for another stamping ?

  2. Do I have to travel before September 2017 ?

  3. Do I get a new visa expiry date?

Thanks in advanceā€¦