Air Canada has both the absolute best and the worst award flight availablity. If you are basic, Prestige (low-tier) or Elite (mid-tier) awards are very difficult to come by, and subject to several blackout periods.

On the other hand, if you are Super Elite (top-tier, 100K/year) you have no black outs and NO capacity controls. As long as the flight is not oversold, you, a travelling companion, or even someone you want to give an award to even if you're not traveling with them, you can get a coach or Executive First seat (or seats.)