Hey, my downstairs hallway light switch is a 2 gang but doesn't control my upstairs hallway light (and just a 1 way for the upstairs light). After inspecting, there is unconnected T&E thats runs to the upstairs light from the downstairs 2 gang switch. Now I know that can't be used as a 3 core but wondering if there is any other options available t0 me to operate the upstairs light from the downstair switch? Many thanks.