There's definitely a degree of variability in the CdG on the dials - probably there was some hand finishing involved in the process.

If you look carefully here (with apologies for the poor snapshot but it was one I had handy of two barrels together to demonstrate this):

you might just see that the left hand edge of the middle panel on the champagne dial neatly bisects the 11 o'clock marker and enters the 12 hour register on the 1 hour hashmark. That gives a shield and Carrera text neatly centred in the middle panel. On the fumé dial, however, that edge just clips the 11 marker and hits the register nearer the 1:30 hour marking. As a result, the shield and text are closer to the left edge of the centre panel just as on your Cal 15.

Just within the natural bounds of variability, I've seen it on blue and fumé dials but not the champagne. I've not seen any where it's offset to the right either. A couple of mm's difference makes quite an impact on that alignment but I don't think it really detracts.