I am refitting a kitchen and have double 13amp socket on a ring main (two cables) behind a floor level fitted cupboard. I want to move this up above work tops, should I add one 2.5mm cable into the socket (this socket would not be used as it is behind the cupboard) and form a spur. Or joint a new length of cable to each using 30amp Choc block terminals inside the socket box covered with a blanking plate. New cable too be cut in and capped.