error-pages/404.php

@@ -14,6 +14,12 @@
 
     <h1>Oh no!  That page can't be found</h1>
 
+      <p>
+        If you got here from a homescreen icon on your device, you will
+        need to remove and re-add the button due to major upgrades to
+        the Athena application
+      </p>
+
       <p><a class="actionbutton" href="/">Go back to the homepage</a></p>
 
       <h3>404 - Not Found</h3>