Eligible Number of Years on H1

I was previoulsy on a L1 visa for 3 years from Feb 2009 to Feb 2012 and went back to for L1 extension which did not happen. My H1 was filed and got approved and start date is Oct, 2012.But I entered US only in May 2013. My visa is stamped till Sep 2015. Will I be able to get an extension for another 3 years and get the full term of 6 years.

h1+l1 = 6 years