L2 to H1 B conversion. Will file for H1b on apr 2014

Hi i have valid L2 visa till Apr 30 2014 and I 94 till Sep 30 2014. Spouses L1B visa is till Apr 30 2014 and I94 till August 14 2014.So, I got my EAD till August 14 2014(based on spouses I 94). I am planning to get my H1b done on Apr 1 2014 as premium processing. I heard that the h1 start date will only be from Oct 1 2014. Since, my EAD will expire Aug 14 2014, can i request for earlier start date in my h1? Appreciate your help on this. Many Thanks!