I had this in my 24 Cupra Leon. It requires the SOS module to be replaced - that's the only fix unfortunately.Its recently been serviced so I'm assuming its on the latest software.
Would you know what the latest update is for a 73 plate so i can check please?
I haven't noticed what colour the SOS light is when this happens but i will look the next time.
I will email the link you have sent me and vent my displeasure and see what happens as i have very little faith in the dealership.
Thanks for your help.