That's terrible and really puts indie developers at risk. One small change on Apple's side and your business might not survive. Hope Apple fixes it quickly!
What's clearly broken here is the sudden changeover. If things were working correctly, placement would change gradually, based on a shift in the marketplace. From the information in the post, it looks like Apple just decided, "Okay, your turn is over! Next!"
It's another sad case, of many that seem to have hit the HN front page in recent months, of a developer having to resort to social media (i.e. blog, Twitter, HN, etc.) to try to get sufficient attention to get a problem fixed by (Apple/Google/etc).
This is a risk that has always existed and is not particularly new - how many web-based businesses have died due to changes in Google's search algorithms, for example?