We booked a bounce-back
free dining package in November 2013 for late-September weekend this year. At the time, we were thinking we wouldn't actually be able to go. Since then we bought into DVC and instead are hoping to go with "freebee" points during mid-October instead (long story). I have yet to cancel our reservation because even that is not certain.
That's a rather convoluted way for me to say: I only booked the bounce-back because I knew I could cancel and get a full refund at least 45 days before my arrival date.