Don't make a rookie mistake like me a few years ago with GUC's.... don't actually select them until you know you have a flight you can attempt to use them. I got my first 4 right away after hitting DM the first time.
Then I didn't have international travel for 4 months. Then I did have something planned and waitlisted for 3 months. Then they didn't clear even at the gate... almost expired worthless.