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Hello my name is XXXXX XXXXX I will help you with this. Please note that I am a working Solicitor and may be on and offline as I have to attend Court and meet with clients, even at weekends. As such you may not get an instant response when you reply, but rest assured I will be giving your question my immediate attention upon return You do not need to wait here as you will get an email when I reply.
The law requires that they give you access - but what the law does not do is give you unfettered access.
This means that Southern can give you certain dates.
In terms of re-configuration again there is no law that requires them to do this.
As it stands they can ask you to specify dates on which you can have access.
I am sorry if this is not necessarily the answer you are looking for and certainly not the one I want to give you, but I have a duty to be honest.