The short answer is probably not, although you would be well served to have your situation examined fully by an attorney. Had you filed an I-485 that has been pending for 180 days or more, you might have been able to "port" your employment and keep the GC matter alive. However, without the 485 in the queue, this will be an unlikely option.
I agree with my colleague.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship. Answers on Avvo can only be general ones, as specific answers would require knowledge of all the facts. As such, they may or may not apply to the question.
If you are qualified for an I-485 file it with an application for employment authoriztion. with an EAd you may be able to work for who ever you want. However, if approval of the i-485 is based on your current visa and employment situation this will not work for you. The best step for you to take is to consult with an experienced employment immigration attorney.
Assuming you were in lawful status and could satisfy the EB1 criteria when you filed the I-140, you should have filed the I-485 and I-765 concurrently with said I-140. However, in view of your current change of circumstances, I strongly suggest you consult with an experieced attorney as the filing of an I-485 at this point and its denial (should it occur) may well bring about very adverse consequences.
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