Layoff- COS from H1 to B2 and then move back to H1

USA H1B
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1

Hi all,

I got laid off. I am on H1B and my grace period of 60 days is going to end soon. I am planning to move to B2 using I539 form filing online. When I find a new opportunity while on B2, should I need to wait until the H1B transfer is approved to start the new employment or can I start working on the H1B receipt notice?
Also, is it better to change to B1 or B2 to stay in the US and find a new opportunity?
Please advise.

2

This has the information:

3

Thank you so much for the information.

4

Hi Anil,

What are all the documents that needs to be provided as evidence for H1B cos to B2?
While filling I539 form online, I see that I94 record, and written statement are mandatory. Also, there is additional evidence column to submit more documents. Please let me know what other documents are needed.
Thank you!