Good question, I always thought that even if you completed a quest - if you didnt turn it in but leveled up afterward, the xp reward would go down.
For instance, if you look up a quest on Thott, it will say it gives been X and Y xp. If you completed it at level 10, you may get X but if you wait until 20, you may only get Y. -- www.pulsetoday.com -- marketing forums!
