AeroMar,
I think you can safely do the trip in one day, if you can find flights with the right departure times. Fly in 27th anytime and check in at the hotel. Sleep (if you can control the excitement). Do the interview on 28th, fly out the night of 28th. I recall the June interviewee at AUH said its 2.5 hours long, so flying out at night should be fine. They won't bring the session to an end too late at night.
If its anything like UK interviews (not just aviation interviews), then 2.5 hours will probably mean 1pm start, 3.30pm finish. This allows people to depart in the morning, and return home by night time.
Q