Wow that is one detail and comprehensive interview process. Considering the checks your DH is going through I would say he is in with a good chance. I would definitely not be resigning or mentioning it to his boss until he has the position. If he has to leave when on holidays that is the way it is unfortunately. He can always ring up and make a phone appt and resign over the phone to his boss while on holidays. Best of luck for your DH.