The guidance follows the U.S. Department of Homeland Security's (DHS) publication of a Final Rule on July 17 that replaces the decades-old Duration of Status (D/S) system with fixed periods of admission for F, J and I visa holders.

Under the new regulations, F-1 student visas and J-1 exchange visitor visas will be granted for a fixed period of up to four years, while I visas for foreign journalists will be limited to 240 days, or 90 days for Chinese nationals.

Columbia University on Wednesday advised international students to return to New York before classes begin on Sept. 8, noting that the Final Rule has a 60-day implementation period before taking effect on Sept. 15.

Students at the University of Pennsylvania. Photo from the university's Facebook page

The DHS rule also reduces the post-completion grace period from 60 days to 30 days. Students who need additional time in the U.S. will be required to file Form I-539 with U.S. Citizenship and Immigration Services (USCIS) to request an extension of stay.