Theoretically speaking h1b is out of status immediately after being
laid-off. In reality,
USCIS often ignores one or two months' of gap and approves h1b transfer with
an I-94 card.
However, the lawyer will certainly suggest h1b workers to go back to their
countries for
visa interviews so the out-of-status period is kind of covered up.
I don't think there is any real consequence if one skips the visa
interview after getting h1b
transferred. But that's only my personal opinion.