A quick read of the thread the one above fixed itself. Have to see whether yours does. The infotainment systems in these units freeze up you can do the on / off hold till the Seat / Cupra logo comes up but as said 20 minutes power down with the car locked or sitting inside but not touching the infotainment is the same result.
Shaky Linux programming leads to the program getting into memory it shouldn't be in which gives the odd results. If it doesnt fix itself or the reboot doesn't work then it will be bust.
Yes, I think you are correct. I've just been out again having left it for a couple of hours and it's working once again. Phew.