title: iBeacon background monitoring stops working
body: <p>I have an app that monitors iBeacons entry/exit events. When it receives an event it forwards the event off to a server. The app continues to work (e.g., the server continues to receive updates) after the user minimizes and/or force closes it (so it works correctly in the background).</p>
  
  <p>However, after a phone has been away from any iBeacons for a sufficient amount of time (e.g., overnight) and is brought near iBeacons again, the app stops receiving enter/exit updates until the user opens it up again (brings it into the foreground). If the user minimizes/closes the app at that point, updates continue to work correctly in the background.</p>
  
  <p>Is anything that I need to do to allow long running monitoring updates in the background? After a while does iOS stop background monitoring?</p>
  
  <p><em>Note: I am running iOS 9.3.1</em></p>