Delay node with delect flush manual or timeout

Hi
I have flow:

I set delay node in 10s, if have mqtt out reponse mqtt then i send flush [Delay node] for [http reponse node] immediately, but timeout 10s then Also http response with body timeout

But I can not detect the output of Delay Node is due to Flush or Timeout for http reponse node is value Ọk or request timeout sensor?