The standard rear suspension had a spring operating on the lower arm and separate shock absorber operating at the hub. In 2016 the standard sport springs were removed completely, changed to a coilover shock absorber with adjustable damping, spring rates and ride height. New wider turrets were made to house the larger diameter shock with spring, a simple polybush top mount fixed it to a single slot in the new turret. it worked okay but could be noisy and was not precise.
So in 2021 the turrets were modified further with metal spherical bearing top mounts, clamped to transverse slots in the turrets that now allow precise camber adjustment.