What it is
The grace period is the lesser of 60 days and the period until your status expires, measured from the last day worked. You cannot work during the grace period, and a transfer petition filed inside the window keeps status. Some employers count the termination date as the last day, so the clock start is a written fact.
What to do about it: Ask for the termination date in writing on day one. The petition must be filed inside the window, and the date the employer reports to the government is the one the clock uses.
Plain-language description of US practice, not legal, tax, or financial advice. The paired guide carries the citations, dates, and thresholds; the state pages carry the local windows.