Simon,
This can be done to an extent with scripting however this would be a complex script that would have to involve professional services..I would suggest inquiring with our sales department for further assistance on this process of professional services if the below is not enough to get you started.
We can poll the IP address periodically to see if there has been a change. We can also switch to another session by emulating the shortcut keypress to switch sessions. We cannot trigger a connection but if the session is set to autoconnect to a particular host profile then that will get triggered as soon as the session is active.