I have a non-immigrant O-A Visa. issued 10 November 2012 which states "enter before 9 November 2013. I entered the country on 12 December 2012 and will leave 14 March 2013. If I enter prior to 9 November 2013, how long can I stay. Can I enter after 9 Nov?

I have a non-immigrant O-A Visa. issued 10 November 2012 which states "enter before 9 November 2013". I entered the country on 12 Dec and stamp says I can stay until 11 Dec 2013. I will leave on 14 March 2013 and get a departure stamp for that day. I have been told several things. If I enter again prior to 9 Nov 2013, How long can I stay,i.e., how will my passport be stamped. If I enter after 9 November 2013, will I be given another year or have only 30 dyas since my Visa says "enter before 9 November 2013 ?