title: Problems with Push Queues on Google App Engine Managed VM / Flexible Environment
body: <p>I am having trouble with using Push Queues on Google App Engine's Flexible Environment (formally named, their Managed VM Environment). I am receiving numerous <code>404</code> <code>Instance Unavailable</code> (see picture below). </p>
  
  <p>After a bit of sleuthing, I believe these errors may be because I am adding a task to a task queue, then deploying a new version of the Flexible VM instance. The taskqueue that I previously pushed is locked to the older instance, and can no longer run. Is this how taskqueues work with Flexible VM? If so, how does one use push taskqueues with the Flexible VM?</p>
  
  <p><a href="https://i.stack.imgur.com/EZy3j.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EZy3j.png" alt="taskqueue instance unavailable"></a></p>