In a few weeks, I'll be speaking at a conference in Toronto. Several weeks ago, my assistant made all the flight and hotel arrangements. 
Today, she told me our travel agent accidentally canceled the trip, so she asked them to re-book asap so we can still get 21-day advance pricing. The flight we booked today cost half the price we paid for the ticket booked several weeks ago.
In light of all the airline bankruptcies and rising fuel prices, this makes no rational sense to me (not to mention I thought you were supposed to be rewarded for booking early - not penalized).