I don't know but I was calling in this morning to book a flight that wasn't able to be booked online. The agent could not even see the flight I wanted. It was LH 471 on 11/8. They kept telling me the flight did not exist. I told them I was on united.com and was looking at it. They ending up just having me book the "non existent" flight and then tacking on the connection that I wanted. Still it was something I had never ran in to.