So just to update everyone here, I got the switch replaced and I had a bit of a shock as to the reason why it was broken. It was wired up incorrectly and so much power was going through it, it melted the inside. It was getting hot to the touch. I don't know if the electrician was being dramatic (he's a well trusted guy) but he said if nothing was done about it then it was likely to start an electrical fire within the next few weeks. And we all know how hard they are to put out if you don't have the right equipment. I feel like we dodged a huge bullet there!
On another note it looks like all our hard work is paying off and we managed to get our usage to 8Kwh per day. Which is about £2.75 per day....nice!
This was really hard going, my aim was to reduce as much as possible without actually changing our lifestyle. The only real change to what we do on a daily bases is using an extra remote to turn some smart plugs on/off and the end of the day before bed. It's incredible we managed to reduce our usage to under half what we used to use. I was also surprised how long it took EDF to register the change in usage, i still think they massage the figures a bit by mixing readings with predictions on usage like they use an algorithm of some kind, it's too late to check that now so whatever.
This is my day's usage
The spike was because of the washing machine. but the baseline now is about 0.2-0.25kwh now