TT BLK SUB or TT BLU SUB

[MAXI DIAL]

Hi,

I don't know much about the submariner history, but I know that Rolex introduces new models in 18k/TT first then it introduces the SS models the following years.

Now...
1- Which SUB came out first?? Was it the 18k/TT or SS model???
2- Which came out first??? Blue, Black or Serti??

If Rolex decides to introduce a new shape SUB next year,
3- What color will come out first??

Thanks