Today I drove to Winchester Services.
I was meant to be going to Kent but the coolant dash light came on half a mile ahead of the services. Very odd as the coolant has been refreshed about 100 miles ago when a new thermostat went on and I had an inspection 2 done! I let it cool and open the filler cap and there is nothing in there let alone the stick thing being on low, it was just resting on the bottom of the filler pipe. Lots of splashes of coolant all over that quarter of the engine bay.
RAC man turns up an hour later and it's magically full to the top of coolant! The dash light is on still but the thermostat was sticking to 90c and no coolant splashing out anywhere. He was happy for me to drive to my local garage back in Southampton and they had a proper look and said the bleed nipple broke and was opening closing, changing the pressure etc all the time upsetting the sensor. Got that fixed in about 30 mins.
I'm going to Kent tomorrow!