M4 CS CCB Brake Pad Pitting

[JC 73]

Hi all, wondering if anyone else has come across this.

Car has 12k miles on the clock and the pads have 11ml remaining so around 90% of their expected life.

The CCB's have always squealed as you would expect but on Friday last week the front drivers side brake was making almost squealing / grinding noise. Fearing the worst I took the car straight to the dealership as I was concerned something was stuck in the caliper. The dealer stripped the brakes down and there was nothing stuck and no damage or scoring to the rotors but there was this pitting on the pads.

BMW have suggested the brake pads have overheated to cause this pitting and refused a warranty claim.

As they didn't have the pads in, they built the brakes back up and assured me the car was fine to use whilst I waited for the parts to come in.

After the breaks were built back up, the noise has now gone and there is no noticable issue with braking and I am wondering if it was a result of salt residue etc due to the time of year and the fact the car is used as a daily driver.

Has anyone else experienced this?

Am I at risk of damaging the rotors or is the car fine to use?