H1B Extension/Transfer related queries when staying in either India or USA.

Hi,I have few queries regarding H1B transfer(as per my knowledge, it is same for new H1B petition from a different Employer. Pls. correct me if wrong). It would be great, if you can answer these.Details about Visa: I received my H1B in Sept 2012 for 3 years and is expiring in mid Sept 2015. It was initiated by Company A and during this time I travelled for the same company and stayed in US from April 2013 to Nov 2014.Queries:1. What is the best time to start the H1B visa Extension process, before it gets expired.2. Can the extension process be initiated from any of the Locations i.e. either India or USA. If yes, then how much time does the processing take for both locations and do we face any glitches or delays in processing. How much time does the Premium process take?3. Which location is better to do H1B visa transfer/extension, India or US and why?4. If I join company B, then I suppose my current visa status does not stand valid. Is it correct? After joining Company B, how much time before expiring of Visa(by Company A) should we start the Visa process for H1B transfer through company B. [Mine is valid till mid Sept 2015(as per current visa stamp on Passport). Does the H1B transfer mean the same even if applied after Sept 2015 by company B in India/US].5. The H1B visa validity they say is for 6 years, does this mean the time one stays in US or time from H1B petition filing? [Suppose a person stays for 2.5 years in US in the first 6 years. Is he still allowed to stay for 3.5 years.]Thanks, please do answer.Regards,Another H1B traveler


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