Megastar App Ranking/Download, page-140

No idea, we're not privy to that information.
All i can think of is they want to build momentum near the end of the competition for what comes next. Could be a short monthly comp, different genres only, etc...

Whatever the case, there won't be a million dollar carrot dangling for performers to join.
And virality in social media usually happens only once, so don't waste it at the start and people lose interest in the app after the finale. Do it near the end and hope it builds on to the next comp..

Just guessing...