Non-Profit to Profit ! PLEASE HELP !!!

[ark1211]

I AM POSTING THIS AGAIN AS I DID NOT RECEIVE ANY RESPONSE ON EARLIER ONE : PLEASE HELP !!!
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Hello All,
I tried to find the answer in the FAQ's, but couldnt.

I have a couple of questions :

I received my H1B visa under exempt category (from my university). Now I am looking for a new job. This means when I land a new job, that employer will have to sponser my H1B. My question is:

1. If I get a job in a company and that comes under exempt category, Does the company have to file anew H1 or they have to file a transfer?

2. If they do file a new H1 or a transfer, they will have to do it on/after April 1st, and once they do it, when can I join the new employer? Is it after they H1B is approved, or I have to WAIT till October 1st to join them.

In other words, If the new employer files an H1 (exempt/non exempt), Can I join him imm. after I receive my approval, or I have to wait till Oct. 1st.

Thanks a lot,
You guys are always very helpful, prompt !
Aniket.