H-1B to F-1

[kk77]

I got my H-1B in lottery this year. I have worked with my employer for 1 month. I am getting admission in PhD program starting Fall 2009. Let us say I file COS to F-1, and get F-1 while I am in US. God Forbid things don't work out and I have to go back to H-1B, with a new employer. Can I use the same no. or do I have to go for a lottery again. How long is a number for H-1B valid. Is it 6 calendar years after getting selected for lottery or 6 years of using H-1B . Please help. i tried researching on other posts but could not find the answer.

[orion]

Yeah, looks like you really tried searching way too hard

You can use the same, no need to go through lottery again.