Whatever you do, be flexible and don't be afraid of code share designations. My wife and I and another couple, are booked on a 14 day Athens to Rome Cruise with a 3 day pre-cruise land program in Athens this fall. Our initial requests for Delta flights out of Birmingham, AL and Mobile, AL connecting in Atlanta, and returning from Rome also connecting in Atlanta to Birmingham and Mobile were basically offered with a very significant up charge. It was suggested by TA to look at the same flights the day prior. We were offered the same flights, a day earlier, with no up charge. Both couples booked first class to Atlanta from Birmingham and Mobile. My Atlanta to Athens tickets are on a KLM flight (operated by Delta) and the other couple booked on the same flight, except it was the actual Delta flight Atlanta to Athens. Return flights are all Delta Rome to Atlanta and then on to Birmingham and Mobile. Go figure.