Cheers guys, I had already started looking at Octopus Intelligent Go, I got a referral code for Octopus and should be switching to them on the 1st August. They do seem the best choice going to be weird getting into the habit of putting the washer/dryer on overnight like the grandparents!
The utility warehouse offer of the day/night rate have been included below for comparison, This is in the North East.
Gas
Unit rate: 5.205 p/kWh
Daily standing charge: 29.922 p/day
Electricity
Unit rate (Day): 27.817 p/kWh
Unit rate (Night): 7.014 p/kWh
Daily standing charge: 67.397 p/day