score:4
So, just called the CBP Info centre, as well as the CBP at JFK airport
According to both sources, if his visa is a combination C1/D and B2 visa, then he can stay after his contract finishes without further ado.
If, however, the visas are separate, then once his contract finishes, if he wishes to remain in the US for a while as a visitor, he has to:
or
USCIS
ATTN: I-539
2501 S. State Highway 121 Business
Suite 400
Lewisville, TX 75067
Upvote:3
It sounds as though he has a C1D & B1/B2 dual visa. It is not uncommon for crew members to apply for, and be granted this dual arrangement, which exists only for C1D and B1/B2 visas.
Were he to enter the US solely on the C1/D, he would be allowed to remain in the US for 29 days (even when it is after employment has ended); entering on the B1/B2 would enable a longer stay.
Crew members who will be entering the United States during time-off between flights or cruises should also obtain a B-1/B-2 visa to use during these personal/vacation days. Applicants applying simultaneusly for both a C-1/D and a B-1/B-2 visa pay only one visa application fee.
Either way, he shouldn't encounter an issue.