Frequently Asked Questions - Status
When used in relation to immigration, this is another name for being LEGALLY present in the USA
See clip from Attorney Rajiv S. Khanna's conference call video that addresses this question.
If you get laid off on H-1B there is no grace period. You get laid off today tomorrow you are out of status.
In my view, it is unsafe to travel on an existing visa after being out of status. If they become aware of your status problems, CBP, upon returning, can turn you back at the airport, or worse, even formally deny you admission thereby laying a five-year bar against reentry.