[russellw]

Yes, I will be having a conversation with Continental about it as it looks like a delamination in the sidewall.

I always check and set pressures the evening before a road-trip and they were spot on at the recommended 40PSI cold and that damage doesn't look to be heat related anyway.

In fairness, those rear tyres had already done 36,755 km on the front before being moved to the rear where they have done 15,200 before that failure so after almost 52k km, there was still plenty of life left in them. Indeed, the one off the RHR is going to be fitted to a full size alloy rim (I bought a set of 4 2H ones) so that it can have a full sized spare in future.