Thanks for your replies Wigwam, much appreciated.
I have now switched to Octopus Go tariff, which provides me with 5PKW charging between the hours of 12:00 and 04:00 which is enough to fully charge the XC40, and costs me about 50 pence for 27 miles which I am very happy with.
The Volvo app was supposed to do timed charging but that doesnt work, so i got a wifi plug outside and set the times via the App.
Overall, very happy with it.
Couple of things I would change are the charcoal interior of the R-design pro model, I find that quite claustrophobic, coming from a car with panaromic glass roof which let a lot of light in. and maybe the reversing camera, which was part of an expensive options package which i couldnt afford, but not really an essential.