Yup. That was cited as a fact a while back in this thread because one of the writers (in an interview) was apologizing for being too vague with their product, now that the sequels seem less likely.
Thoughts I had while walking to lunch this afternoon.
1. If arriving in history instantly rewrites the present as it stood where you left, then it should have been impossible for Skynet to send three Terminators (one at a time) and more impossible for Kyle to follow the Terminators and even further more impossible for Kyle's crew to blow up the temporal complex after he left for 1984, if the immanent paradox should have caused this 2027 (whatever!) to stroke out.
2. Skynet faked sending a Terminator back. The T-800 in 1984 that Kyle met and fought was from an earlier different timeline that dissolved the moment it back stepped, and Kyle's Skynet wanted it dead. Either Kyle's Skynet was trying to save humanity because it was having cold feet at the 11th hour, or Skynet was tricking Kyle into fighting an earlier timelines Skynet for it, but that would most probably mean that there was a third front in the war that humans were two dumb to notice. There had always been two Skynets (or in this curent renovation of timeline there were two Skynets.) but all that would do is create a third renovation forcing the Skynet in charge of the temporal skynet to commit suicide... Although John Connor had already killed that Skynet, so it's story was over, but it's safer to send a human back with bad intelligence, rather than to send a Terminator back because that only creates more Skynets and a more fractal AI civil war.
3. There's an information buffer on the transmitter. No one was sent back in time until the buffer was full. 2 T-800s, a T-1000 and Kyle. Zip-zip-woosh! The present started changing after the buffer was unloaded and all the time travellers from the first two movies were sent back to their prospective temporal co-ordinates.
4. Temporal null field. Changes to the timeline sop when it his the temporal shielding keeping the Temporal Complex static from reality editing, despite have the wrong history and wrong future forever so long as the shield/field holds. A Faraday Cage for time if you will.