Official Word:

August 2021 will see the arrival of the new M xDrive-equipped M3 and M4 Competition models, for the first time ever. The additional traction will enable the full 479 lb.-ft. of torque to be used to a greater extent during both acceleration and dynamic driving. The fully-variable, rear-biased system distributes torque between the front and rear axles via an electronically controlled multi-plate clutch. An Active M differential takes care of torque distribution at the rear axle....Read.