Nice review. Thanks.

Just as a note: To the best of my knowledge, the reason for Rolex to change the caliber 3185 to 3186 is not only the PB balance spring, but also a new implementation of the solution for adjusting the hour hand.

Similarly there are new caliber numbers for the DJ2, DD2 based on a larger diameter on the date disc. The new Explorer 214270 has a larger diameter base plate, which is also the reason for a new caliber number.

So, changed function, implementation or dimension implies new numbers.

Best,

A