When are they increasing the level cap and/or adding new content?
If it follows the way that last weekend went, they'll be adding things and changing playlists throughout the test. The level cap is going to increase to 30 (fairly sure on this, can't remember where I read it but note that you can see the level requirements for everything up to 30) on Sunday if I had to guess. Pretty sure the updates happen at 10AM west coast time each day.