Turns out we weren't the only ones obsessing about alternate timelines in the Terminator universe. Commenter Leland Rzepecki covered a giant whiteboard in his dorm room with an elaborate chart. (Click to enlarge.)
I love this chart so much! It's kind of sad how much of it makes sense to me instantly. Like when Leland writes "pretzel," I know exactly which elevator-fighting Terminator he's talking about. Leland says he was inspired to create the chart after he became obsessed with Terminator: The Sarah Connor Chronicles and decided to make it all fit. He explains:
That scribbling at the bottom is from when I realized that time in Terminator must be cyclical, because that's the only way to explain how Derek and Jessie can be from different futures but be in the same timeline now. The slash in the middle of the line is Judgement Day. Some of that stuff at the bottom was showing my roommate how Derek would have had to skip a timeline using my linear "domino" model, and I couldn't think of a reason why that would happen.
As for the 12:00, 2:00. I was explaining how we could be seeing both futures in the show. The analogy I was using is that at 12:00 (the clock times are just to make everything relative, if that makes sense) Derek goes back in time, and causes changes to the timeline at 1:00. Then at 2:00, after Derek makes changes like killing Andy Goode, Jessie travels back in time. So even though Jessie came from the same time as Derek, she came later, in more than one way. Does that make sense?
The color coding: Black is pre-Judgement Day stuff I'm sure of, green is Future War stuff I'm sure of, and red is the blurry stuff I can't really prove, but makes sense to me.
My major is Game Design, and I don't recommend it, haha. I've always been a lot better at "fake" science than real science. I love movies like Primer where you have to keep a lot of timelines straight in your head though, so all of this came pretty naturally to me.
I totally want this to become an art project, with different people doing their own charts of Terminator continuity. We could have celebrity Terminator timeline charts - I would kill to see Arnie's.