Blanket L1 information

[mynick]

I have two questions

Background
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I'm on blanket L1 B (specialised knowledge) visa. The visa and petition/I-94 is about to expire. I have to visit India. When I would come back my visa and I-94 will be expired. I can apply for an I-94/petition extension before I leave.
A sub clause about my blanket L1 is that it was issued for a client A. Now I'm working for client B. When I come back, i would continue to work for Client B. My Indian employer does not change.

Question 1
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Is their any rule that says that I will have to apply for new visa instead of just a restamping on the same (extended) petition. My friends feel a new visa is required since there is a change of client involved.


Question 2
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Assuming that I have to apply for a new blanket L1 visa, is their any rule that would say that I have to apply only after my current visa is expired. (I'm able to get a visa appointment date in consulate for April 10 while my visa expires on April 20 and it is very difficult to get an appointment date of choice).

As usual, this is URGENT!!

[mynick]

It seems that my situation is quite unique since nobody has replied to it. Guess, I should speak to an attorney. Anyoe knows how to find good attorneys who deal in visas.