They increased tire pressure so that the tires would last longer than last week, but now blistering happened quite aggressively. 

It could be the aerodynamic of their chassis. When a tire is under load, the shape of the tire changes, and that, throughout the race. It could be that Red Bull's chassis is better suited for this, and their aero permits better cooling of the tires.

Just my guess...


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2018 White 911 GT3