We booked a trip which included airport transfer to the hotel. Just wondering, what is the most important item that the travel company needs to know: flight number or est. time of arrival? In this case, our flight number changed but the arrival time didn't. We didn't even noticed that the flight number changed. They didn't pick us up at the airport because we didn't tell them the flight number changed. So we waited at the airport in Lima, Peru. Fortunately there were helpful people there who called the travel agency on our behalf. We were finally told to take a cab to our hotel and now the travel agency won't reimburse for our cab fare, which was alot cheaper than what they charged us for the transfer.