I want to add two sockets to a ring main in a bedroom. I\\\'ve done one via a 30A junction box on the ring main cable I accessed under the floorboards just near an existing socket. As the existing socket is on the ring there are two cables coming from the socket. One of which I have put a junction box on for the first spur. Can I add another junction box and spur to the second cable of the ring that is connected to the socket?