H1B - After 6 years


I was on L1B from April 2010 to October 2012. I was then on H1B till June 2016. I am back in India for my cool off period. My question is since my H1B was filled on October 2012 does that mean that my H1B petition is valid till October 2018? Can I apply for H1B Cap Exempt after the 1 year being completed in June 2017?

If I do apply for that what is the process to change from H1B to a H4 Dependant EAD, since my wife’s I140 would be approved sometime this year in December?