回复：If I get denial, when must I leave US?

If you can find another job quick and file a H-1B transfer and get an H1B approval with new I-94 , you will be no problem in status even if B2 is eventually denied. If the B2 is your only application pending and it is denied, you become out of status at the time of deinal and need to leave quick.
Detail arrangments: list your toruist plan, and your arragement for back to China after the extended period is finished. The finiancial support for the plan.
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