Hi, I think I helped you just before you left.
1. Will there be any issue in port of entry, since my old visa is revoked and existing has a issue date in sep?
Tell me about the LCA. What is the start date on that?
2. Can i continuously work legally in existing project even my old visa is revoked and existing new visa annotation issue date is from sep 2017?
An E3 is different. You enter on that visa and you have to work for that employer on the visa you enter with. You would have go to work for the new employer.
I really am not concerned with the annotation. The CBP are going to go by the issue date in admitting you for work for the employer. The concern I have is the ability to work is based on an existing valid LCA for you. So your LCA has to be valid from now, not Sept. for you to enter to work for the employer on your visa.
You cannot work for the old employer.
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