They would probably conduct an emergency brief prior to flight for the possibility of a significant system failure which would normally be a return to the point of departure in the event of a fire or a major cabin emergency, but in the case of Jersey, the nearest suitable in the event of a flap fail would be Bournmouth since Jersey has a short runway.
Having made that decision prior to takeoff, it would not be wise to change the plan for engineering or commercial reasons as the crew would be too busy planning the approach into Bournmouth to contact the company for commercial guidance because these requirements are generally thought to be less of a priority than flight safety.
Of course it won't be long before a call to maintrol, crewing, ops, and the handling agents will be SOP before running the QRH!!
Maybe a quick show of hands in the cabin would be in order too just to complete the picture of the ocurrence in the event that the crew and their hodful of paperwork need to take a trip to the fleet office.