the CBS system uses the DSC system and some other factors to determine mileage remaining based on how often and how hard you brake. it also uses a dual stage sensor that will alert the car of preset thicknesses.
if you drive more conservative than before, it is possible the CBS would add life to the distance. have you been doing a lot of highway driving recently?
just noticed you mentioned squealing, look at the face of the rotors (dont forget the side on the inside of the car), if you see any circular gouges something is wrong.
2006 330i - Jet Black - 19" E46 M3 wheels - HR Sport - 188,000 Miles...