1. That's uncertain. If you are outside the USA and you got your H-1B but you didn't get it stamped, will consider you still subject to the quota. I personally think if they say you can't get an exemption from the quota and you got to get a visa stamping there is really no support in law for that viewpoint. So you can try that's all I can tell you.
2. You don't have to leave USA to get H-1B status if you are maintaining H-4 status.
3. If you got three years remaining on your H-1 or more you will get a three-year H-1 and if the project is for 3 years.
4. Many months.
5. If your EAD is valid until your H-4 is changed to H-1 you can continue working. Once you are exempt from the quota you don't have to go back to the same employer. More...
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