Well, according to John's voice-over in T4, SkyNet has stepped up its plans and created the T-800s sooner than it would have in the original timeline.

Anyway, in 2032, the T-800 and T-850 models are obsolete (And now I have Arnold Schwarzenegger's voice in my head, saying that very same thing. Damn. *g*)

Now if I could just figure out how to kill off Kate in 2019 while having a good explanation for the events of 2032 being told as they were in T3 and not creating a paradox...