When booking award tickets its always best to be flexible. The more more flexible you are the more likely to get what you want. With southwest airlines there are no limits to the tickets that you can get with your miles(no black out dates or flight limits)
We are planning a trip to Cancun over spring break. We wanted to travel on 3/26/16. When I look to book our tickets I see this:
Over 40,000 mile for a one way ticket is way too expensive. So i decided to fly out on 3/23/16 instead. This flight is almost a quarter of the miles cost. The girls will need to take 2 extra days off school for this trip, which is the downside of our date switch. Overall the flexibility paid off though as we have the ability to go instead of canceling.