CAP exemption on H1B expiring on Sep2015, petition not exhausted

[mady135]

I have been in US from Nov2012 (my petition was approved in Aug2012) to April 2015; now I am trying for an opportunity there. As my 6years span has not been exhausted and as of now I spent less than 1 year outside yes; can anyone please tell me whether:
1) I have to go for a new petition and lottery
or 2) I can get my visa stamped via the old petition under CAP exemption and request immediate start date.

My current visa is expiring on Sep 2015