Car has now been returned to Milton Keynes. It wasn't far from Wellingborough, but I stopped for 30 min on a 7kW charger to give some contingency!
Overall I did over 600 miles in the week and spent quite a lot of money charging on EH (Ecotricity Electric Highway)! Efficiency dropped a lot later on my trip, due to weather impacting battery and the driver needing heat occasionally. I still used heat sparingly and wore a hat and gloves. I want heated seats in our Zoe and It is a shame that a heated steering wheel isn't available as an option (it is in Leaf).
Clearly a Zoe 22kWh isn't great for long journeys, but I can see it is great as a 2nd car for short journeys. I would like to venture further in the one we get, so will probably order a new 40kWh. Possibly a Signature model as I would also like a better stereo than the standard one!