I have the same issue. Whenever I select a new zone in jremote it just switches back to the original zone that I was in. I'm using the latest version of jremote 3.21 on ios 9.02 (iPhone 5s). jrmc 20.0.132.
Edit: I just wanted to add that I have no issues switching zones using Gizmo, so it doesn't appear to be an issue with the way my zones are configured.