Shyam Madhavan

Hi all,
I had a question on H1 B. Currently I have my first 3 year slot ending
May 2006.
I am planning to get my next slot of 3 years from May 2006- May 2009.
But I have question. What happens to the time if after one year (
argument sake say May 2007) ; I decide to join School and change from
H1 to F1. Do I loose my remaining (2) years of H1 as it is time
stepulated from 2006 to 2009? Or do I still have the remainig 2 years
of H1 ( as I changed my status from H1 to F1) ?

Please respond if you are aware of the solution.

Thanks