Hello fellow electricians don't you just love EDF. A little story we fitted a new 17th edition consumer unit(fuse box if your not an electrician)any way we found a shared Main Head.Their was two main fuses on for the ground floor flat and one for the 1st floor flat in the same place sharing the neutral.In case your not sure were i am coming from if the residents in the ground floor flat were on holiday and the 1st floor main fuse blew the 1st floor resident would have no electricity until the ground floor resident came home.EDF have told us this not allowed and they will not do it. Monopoly's can do What they like.Rule for them another for us.