The new level range allows experienced players to surpass the level 50 limit. You can play more matches, upgrade superpowers, unlock achievements, upgrade characters, use EXP boosts or purchase EXP offers to reach new levels.
You earn Level Rewards for each new level you reach, just as you did before. You can also earn new rewards that you cannot earn in the 1-50 level range, such as Rainbow Cards.
Once you reach level 45, you can get paired with any player above that level.