I’ve done just over 20,000 miles in my UX F Sport with Bridgestone run flats. Still have 4mm on the front ones and 7mm on the rears. So the front ones will get to the next MOT. In June. I think I drive normally, I certainly don’t spend much time thinking about tyre wear. It’s the sort of mileage I would have expected. I do look at the pressures every week or so and maintain them at 32psi.