M4 updated suspension???

[Timbuktu]

Mav281 said:

The changes that were brought about by BMW are all software related, not mechanical. The suspension/damper parts are the same on the standard M3/M4, CP and CS. Older plate cars had older software and as such the ride quality was worse. However, not all bad news even on older cars as any good coder should be able to install the GTS Gearbox package and update your suspension/damper settings to CS level, it’s one of the more popular combinations in the M3/M4 tuning community.

If you read the M3 Cutters link above I think you'll find that that isn't the case. The '65 plate onwards LCI cars had different dampers.