Can I revert back to OPT with h1b approved?

Question

I was on OPT STEM and valid till September 2014. I got a job and my h1b was approved in Jun 2013. So, I was moved to GAP OPT and my H1b would be starting on October 1st.
Due to some unexpected circumstances, I want to try going back to F1-OPT.

1. Is it possible to do so? what is the process and can we do it quick enough?
2. I got my h1b approved once through lottery system and if I join new company they might sponsor h1b next year again. Will my petition go through lottery system again?
3. Is there a possibility that USCIS may reject my h1b petition next year since I rejected the h1b approval once?

Answer 1

1. Yes, try conversing with DSO and your company
2. No, you can be CAP exempt as your visa was approved before
3. Yes, you can try talking to an immigration attorney.