Updates are dependent on hardware as well - we need to make sure that your phone can handle the demands of a major software update. As far as I know though, the A11 is not on end-of-life support yet, so you might get a software update in the near future.
Always check the Software update tab in your Settings to see if you have an update pending to install. You will also get a push notification reminding you to install an update if you haven't yet.
