Cleeverly looked at mine as mobile. I think it's perfectly sensible to get a car looked at by a professional after 25k miles. Mobile is a little more expensive, but so is travelling to Gloucester. They spotted some issues I hadn't, eg wear on the inside of the front wheels was far higher than I'd realised, despite measuring with reasonable care. For a service I'm in no particular rush, so the wait isn't an issue. Planning to book the next service them as an end of warranty inspection and service, I guess that's actually time critical, so if I need to drive there I can..
I tried to find some HEVRA garages in north surrey, but they seemed spectacularly uninterested in doing Tesla work. And I know Cleeverly know the bits they actually need to look at, it would be very easy to someone to check the tyres and seatbelts, check for a check engine light, shrug and charge me £150