@Da***
That is indeed a company specific visa. :O
If that's NOT the company they're going to work for they can't use it for an extension of stay . :(
They CAN stay until the 90 day stamp they got is up though because a VISA can't be canceled and they are entitled to stay the amount of time they got stamped in on it.
Unfortunately they will need to go get another Non-B for the new company.