To close the road trip here’s the final summary. 1400kms in rain, snow and ice around Spain with no problems charging at 22kw every time.
The last leg was essentially all the time between -1C and +1C but by taking it easy and being gentle with the accelerator I did the 403kms with 10kms extra even including the 1700m climbs and 1500m drops on the way.
UPDATE: I have had a few questions as to why I cut it so close with range (10kms left after starting with 490kms of charge). Well, the software on these cars is very good and you can judge your power use and expected range very accurately so as I came to the last 150kms I could raise the speed without worrying, and for the last 50kms I just increased speed so that I would arrive as quickly as possible with minimal residual range. I could have arrived home with 50kms or more easily, if I had wanted to. END UPDATE.