First of all the moment, your I-140 is approved no matter which category EB-1 or EB-2, the Priority Date is yours to keep that means if you got your green card filed in let's say 2017 and you left this employer after the I-140 approval, they revoked your I-140 and you started another green card in 2020 your Priority Date will be still 2017 because your I-140 was approved. So the moment the I-140 was approved the Priority Date becomes your property and it can be carried across categories, across employers, and across geographical areas. So if you go from a PERM filing in New York to an employer in California and your previous filing was EB-3 next filing is EB2 or even EB-1 you can carry the date of the work petition as long as the I-140 was approved. The moment the I-140 is approved, the Priority Date is yours.
There are limited exceptions unless the I-140 is revoked for fraud, etc., by the USCIS. Even if the employer revokes the I-140 you will keep your Priority Date. In addition to that, if the I-140 gets approved and stays approved for 180 days you will not only carry your Priority Date you will carry your right to extend your H-1 through any employer indefinitely. You will get a second benefit after 180 days and if the lawyer revokes the I-140 you will still get the benefit of both Priority Date and the right to extend your H-1 through any employer. The government has also said if you have an H-4 EAD for your spouse, your I-40 stayed approved for 180 days your wife's or your husband's H-4 EAD is safe even if the old employer revokes the I-140 later on as long as the I-140 stayed approved for 180 days. So if you left but the I-140 stayed approved for 180 days H-4 EAD is safe. That, in a nutshell, is the general law. More
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