brakes replacement; when/how many miles?

my 1M has not been tracked to my knowledge by myself or the previous owner. The car now has 49k miles....i've asked the dealer to inspect the brakes a couple of times and they keep saying they are find. I find the brakes to be getting more rumbly and noisy upon braking-----do you guys know when the 'normal' mileage interval is for Rotor and pad replacements? 55k miles?



my warranty is going to run out in the next few weeks....so i was hoping to have them cover my brakes before that; but it's looking unlikely at this point :/