 That will give you the answer you need to know so you're not landing at an airport stranded, wanting to know whether or not to leave the airport to come back into it. It's not always easy, and it's getting worse, by the way. Okay, here's one from Linda. I'm looking at using Virgin Miles to fly Miami to Charles de Gaulle in mid-November. What's the best time to book, and why does the money for taxes and fees fluctuate between $250 and $413? It seems that it varies based on the amount of miles I am using. Actually, it's not.