Simultaneously, the laws also permit requests for extensions of that stay that are filed with the USCIS before the expiration of the current status. The DOS, acting through its consulates, grants visas - the stamp on your passport. Once you arrive at a US entry point (airport or port), CBP examines your admissibility and decides the period of your stay. A reasonable interpretation normally advanced by the USCIS and DOS is that the law permits legal extensions within the United States if they are timely filed. During the Covid 19 times, it became impossible for most visitors to leave the United States within their allocated times.

Source: Economic Times May 10, 2021 05:37 UTC