Visa Stamping while amendment Petition in "Recieved" state

[amit2]

I have one question, not sure if its been faced by anyone else as well.

My Amendment Petition is in Process and filed on 9th Sep 2015 to USCIS. The result is not yet out.
My Visa department is saying that I can still go ahead with Visa Stamping in India, even if the Amendment Petition is in "Received" State. They have asked me to go ahead and book time for Visa Stamping at US embassy.
My original petition is valid till July 2016 though.

Is it correct that I can go ahead with Visa Stamping (in case original petition is valid till July 2016 and Amendment Petition is in Process and I am not in USA). If yes, till what date, Visa Stamp would be valid?
Please confirm if any one is aware.