How much time i hav to strt with new emp if my H1bCOS apprvd aftr Oct1st

I am working with Emp X in US with L1 valid until Mar-2014. I applied H1b COS with Emp Y and its in RFE.

I have to give notice atleast 2 weeks to my prev. employer on L1. Question is

If my H1B COS approved after Oct-1 , can I still work for 2 weeks with Emp X on L1, becuase I can not resign from Emp X unless i have the approved H1.

pls. I appreciate your response…really confused :frowning: