I have exactly the same issue on my 21MY F Pace. The dealer put this down to wear and tear even though vehicle has done less than 10K miles. If the issue was due to wear and tear then why is the pitting across only 50% of the width of the discs. There are no similar issues with front discs. The dealer did raise the issue Jaguar warranty but they said wear and tear.
I complained to to Jaguar and they advised that they had investigated my complaint with warranty and engineering teams advising that there was no problem other than wear and tear.
This issue is yet another I have had with this vehicle and I am seriously considering cutting my losses and getting rid of the car. I shudder to think what cost I could landed with when the vehicle is out of warranty
