Jimmy, talk to the CAA and get their opinion. We had a similar situation not long ago in which a student got delayed along the route and couldn't get back before our airfield became unlicenced, so we had to fly out and bring him back. We all assumed he'd have to do it again but the CAA said that he'd complied with the spirit of the QXC and it could stand. Not saying they'll say the same in your situation but it's worth a try.