Redirect to pool to bypass SSL offloading for Exchange Hybrid setup - syntax issue(s)

Thank you for your reply mikeshimkus!

You are correct about the iRule: it should be combined iRule.

Could I just insert this into the current combined iRule without reconfiguring the iApp?

      }
      "/ews/mrsproxy.svc"
      pool my_mrs_pool
      CACHE::disable
      return
 }

As you predicted the iApp currently is setup to 'SSL Offload' but looking at the clients CAS servers it's not enabled for EWS.