can I switch companies after completing 6yrs of H1B?

[ReenaS]

Hi,

My current status is as follows:

EB3

PD March 2012

Received I-140 but not close to being current for I-145

Completed 6 years of H1B already

I am interested in changing jobs where they can file my green card in EB2 category so I can get my green card earlier. There are few complications due to my completion of 6 years of H1B and would like your legal advice on implications of changing jobs at this point. Can I change jobs now and transfer H1B? And if so, how long do I have until the new company files the GC (that is if my current company doesnt withdraw my application).

Your valuable advice will be greatly appreciated.

Thanks.