Thanks for asking, Kev! Just got home via 2 AA relays.
Only just got going on the run and some water hit the windscreen. Funny, I thought, is Sam in front washing his windscreen? Next thing I spot the steam and the temp gauge goes from normal to eeeeek in about ten seconds. I pulled off and stopped to cool down but even an hour later it was still overheating and the idle speed even now is bouncing all over the shop.
Still got coolant in the expansion tank though, weirdly.
Really gutted to have missed the fun and broken the car. Great to meet you all though, Nick.