GMT ref 16710 bezel font and 3186 movement question

[aboutime]

Hi all, im curious as to whether there’s a definitive answer to my query, I’ve searched the forum and internet and like all things Rolex related, there’s always a transitionary period so the answer is never clear. Anyways I post it and see what your collective thoughts are:

1) when did the gmt bezel serif font transition to non serif? Feels like around 2003 onwards?
2) when did the upgraded movement 3185 to 3186 happen on the 16710? Feels like 2005-6?
3) would a no lug holes case also coincide with the newer 3186 movement?

My search continues for the late model reference!

Thanks all.