I can't seem to find any literature on expiring content with Android's App Indexing feature.
Let's say you have an app that shows users information on store sales. The store sales are time sensitive - they will eventually expire, and no longer be available. While the sale is available the user can see related search results because the app has used App Index to declare them. Eventually, the sale expires though. The content is presumably still in the App Index, but it's now dead from the perspective of the app.
How does one deal with this? Is there a way to explicitly remove content from App Index? Are App Index entries automatically expired if not declared again within a given timeframe?