[Router] level setting does not work for file connection

I'm playing with the router and like to create a route based on log levels so that only errors and levels above are routed to an error.sil file by the router. The error.sil file is created by the router but no single entry will be written to this file.

Without using a level entry in the connection it works, and everything is written to files based e.g. on app- and hostname.

Is this the expected behavior or am I missing something?

See my test configuration below

        
<route>
  <triggers>
    <host />
    <application />
  </triggers>
        
  <connections>file(filename="E:\tmp\error.sil", append="true", maxsize="102400", rotate="daily", level="error", backlog.enabled="true", backlog.keepopen="true", async.enabled="true", sync.throttle="false")
  </connections>
</route>