I am planning to start MBA this September 2010. I am currenlty on H1B and complete 6 years by October 10. My 485 is pending (Priority Oct 06, EB3) and I got EAD. My company is very supportive and they wont withdraw 140 during my study.

1. Can I study MBA on EAD
2. Would there be any problems renewing EAD while studying
3. Is it possible to choose an job in a different field from what was approved with my current labor?
4. Can I keep the current priority date if a different company files for labor on a different job description? While they process that, can i work there on the EAD from current job?
5. Can I extend/ switch to H1B based after graduation to work on a job thats different from what my labor is currently based on?