This is about FIXING bolt - sorry cannot edit title anymore.

Just found out that there's been a change to the depth into which a crank fixing bolt goes. Talking about the plastic one with flower-like interface that's only used to set the bearings preload.

It got longer:

8.5 mm:
- Length: 8.5 mm (short)
- Type: A-type
- Compatibility: Dura-Ace FC-9000 up to mid 2013, FC-7950, FC-7900, FC-R9200
Note: also fits Ultegra FC-6650-G, FC-6700
- Manufacturer Number: Y-1KY08000

16 mm:
- Length: 16 mm (long)
- Type: B-type
- Compatibility: Dura-Ace FC-9000 models up to mid 2013, FC-R9100
Note: also fits Ultegra FC-6800
- Manufacturer Number: Y-1N218000

Any idea why would they have done that? Were people stripping the plastic threads off by overtightening them? I mean they have no function once the pinch bolts are tightened anyhow.

This is the case on lower lineups as well from my observation.