Job Change - PERM and I-140 approved, I-485 not filed yet


New Member

This question may have been asked before but I couldn't find the answer.

My current situation
1) Currently in 5th year of H1 with employer A
2) PERM and I-140 approved with a PD of Jan'09; I-485 not filed yet - EB3 category
3) Received 3 year H1B visa extension based upon I-140

I am planning or rather thinking about job change
1) Can a new employer hire me under a transfer of H1? How many years would I get?
2) Can the same employer file for my Green Card under EB2 category. I understand that the stage I and II will have to be repeated but can I keep my priority date same if it is a similar category job?
3) Does my stage I and II automatically revoke if I quit job at Employer A? Is there a certain timeperiod after I-140 approval that stage 1 and 2 cannot be revoked?
4) If I can't keep my PD, can a new employer B still file my green card from scratch (assuming that I have a successful H1 b visa transfer), even though employer A has filed my green card before. Will there be any complications?

Any thoughts, advice, experience or recommendations would help.