She checks her little pink watch. "Yeah, that's doable."

Jenn nods again. "Same goes for you, Elizabeth. Back in an hour." (She doesn't say who she's following if they're not, although there's a definite implication she's going to follow one of them.)

"Right."

"Anything else before I head out?"

"Don't die?" Jenn manages to make her tone flippant.

"Promise I'll try my hardest." A glance at the door, a muttered, "Wish me luck," and a check there's nothing immediately outside - 

And she's off.

Jenn finds somewhere she can watch Bina's progress from, and see if the dark wiggly things are following her.

Wigglies do, indeed, follow Bina!

They seem mostly slower than her, at least.

Elizabeth slips out once the way's clear.

Well then. Jenn will have a quick look around to see if she can find roof access, keeping the journal with her, one of the flashlights, and water.

There is, indeed, a metal ladder leading to the roof, accessible from the fire escape.

Alright then. Up to the roof it is for some heavy duty reading.

There's nothing visibly alarming at first glance. Not too many of the wigglies - there seem to be only a few, indeed clustering around Bina, and they're incredibly difficult to see in the dark.

The journal has a sticky note affixed to the front page.

Hey Me! 

So getting this notebook to you, while avoiding any Observed areas, has been a bit of a nightmare. You'd better appreciate it! 

I kid, I kid (but seriously, this truck was really hard to track down!). 

Assuming our time-lines match up at all, and you're in the truck while reading this, you have about half an hour before Elizabeth returns your call. 

Don't fall asleep! And when she does call back, get her to flip the crane to automatic and then RUN. I think if you do that, some really really nasty stuff won't happen. 

Other then that, I won't try to tell you what to do. Eleven tried that with me and it just made a mess of things. We're looping, but everything changes each time. This situation is all the worst parts of time travel with none of the benefits! Hurrah! Weee! 

I could go on, but this is getting pretty long, and I have a Thing I need to go do.

Wish me luck,

- You

If Jenn had to guess, the 'really nasty stuff' was probably Elizabeth dying. Which: go them, they'd prevented without B12's help. She leaves the note tucked where it is, and delves into the rest of the journal.

The first page opens with:

I am writing this journal for my successor because recent events have convinced me that B3 has, systematically and repeatedly, been leading us to our death.

While I'm convinced that's what she's done, I have no idea why. I can't think of a situation where I'd do this, but 3 spent at least a year, maybe more, of subjective time in the Moment, so… I don't know. I don't know why, but I do know that her actions are inconsistent with allowing us to get out of this.

Reasons I think she's messing with us: 

1. The version of the Mathematical model she passed on, is inconsistent with the principles she used to create the greater Devices. This is difficult to tell, but an in depth comparison between their actual design and the designs on the blueprints reveal significant differences. Leading us to…

2. Some of the Devices contain mechanisms that limit their range or effect. These mechanisms have been added purposefully, but placed such that their removal would damage or destroy the device. 

3. She appears to have developed and then destroyed several Devices that would be useful, and has left no notes as to how to recreate them. I believe she developed a method for reconstructing shattered patterns (at an enormous entropic cost), as well as a means of extending n-displacement beyond 466.2 Hz.

For these points, I have proof, proof that I will explain later, at length, in this journal. You'll be able to verify them yourself when you get to the Moment. 

The last point is just a theory.

But it's the one that convinced to write this journal.

I think 3 killed 5. 

Not through omission, directly.

I think 5 found out something that she wasn't supposed too, and 3 scrambled her time-line by entering it on the fourteenth and killing Ant. This would have caused enough stress on the Loop to make the situation untenable, forcing the Botfly to shuffle the Loop immediately.

I know that this isn't supposed to be possible, and we're not supposed to be able to affect things beyond one loop in either direction, but it's the only thing that makes sense. 

My understanding of the order of events looks like this:

4 finds the Moment, finds the first notebook, and Loops. 5's time-line starts, and at some-point she discovers something dangerous, something that 3 doesn't want us to know. 3 uses one of the Devices that she later destroys to scramble 5's time-line. The Botfly Loops.

6 starts, gets to the Moment, and finds the second notebook right away, in a place that 4 must have been several times. The second notebook contains the essay on "Probabilistic Uncertainty in Entropic Time-Loops." The essay that everyone afterwards agrees explains what happened to 5. But if we assume that 3 could reach forward into 5's loop, then it makes sense for her to be able to reach into 6's loop as well. She could have written the second notebook later, AFTER killing 5, and given it to 6 to allay suspicion. 

The Second Notebook is almost all user and fabrication instructions for existing Devices. Aside from the Probabilistic Uncertainty Essay, it has no new theory, no new math, just some formalization on the entropic constant (which I think is probably wrong, and only serves to make the PUETL essay more believable).

And if Probabilistic Uncertainty in Entropic Time Loops Theory was correct, how am I here? How is anyone after 10 here? The number of events necessary to create my own time-line are immense, and as entropy has increased, probabilistic mishaps should have stopped my own time-line, and that of 10 and 11 as well. 

But they didn't. 

The ONLY 'probabilistic mishap' in thirteen loops happened to 5, and that was in a loop with less then 1/300th of the amount of entropy in my loop (less then 1/6000ths of the amount of entropy that B13 is dealing with). 

If the PUETL essay were correct, there is only a 0.00086% chance that I could possibly exist, and an exponentially smaller probability that B13 could exist.

But she does, because I've seen her. 

You. 

This is very confusing to write.

Anyway, it's wrong. It has to be.

Either we believe that 3, someone who managed to do things that none of the rest of us have ever been able to even get close to replicating, got one of her fundamental theories wrong, while also believing that 4 was so unobservant as to not notice a brightly coloured notebook on a table in the cafe, in over THREE MONTHS of walking past it every day, OR we believe that the notebook was never on that table. That 3 put the notebook on the table AFTER she'd killed 5.

If this is the case, then only explanation is that 3 had the ability to reach forward into future Loops, an ability she has never shared, and has apparently done everything in her power, including murder (and suicide?), to prevent us from acquiring.

-The idea that there's a previous Bina working against them seems... insane. But also Very Dangerous. Jenn files a note to ask her Bina if she can think of any reason she'd want to stop herself learning something. (And Jenn finds it Highly Unlikely that any Bina would miss something when she's looking for a solution to something.)

Alright then. Conspiracy theories read: What else does the journal contain?

It seems to mostly be a rebuttal of other books that Twelve's assuming they have access to.

There's at least five different models of time machine described, though, two of them labeled 'historical.' 

Time machines seem to all have at a minimum a power source, a tune-able antenna, and something to handle paradox. Most of them require a piece of the future and the past.

One doesn't.

What does 'historical' even mean when there's time travel involved.

She reviews the information again, but she's not sure what she can do with it, and wants to talk to Bina (...and Elizabeth) before making any plans.

She makes another scan of her surroundings.

That's probably Elizabeth approaching, off in the distance.

No sign of Bina yet.

She's not going to draw immediate attention to her presence on the roof, just in case it isn't Elizabeth. And she's not going to worry about Bina just yet. (She can take care of herself. Probably.)

Definitely an Elizabeth. Exhausted, muddy, with a tear in her hazmat suit she's hastily patched, but alive and probably not bleeding.

There's a sound of breaking glass off in the distance.

(Bina would like to register she was so being extra careful. The pipe adventure wasn't her fault. Extra speedy wiggly is even less so.)

Jenn wishes she had some sort of binoculars or sight so she could figure out what the hell was going on.

Bina has five minutes before Jenn is going after her. In the meantime: Jenn slinks off the roof to meet Elizabeth and do a reassessment of their supplies.

"No serious trouble?" she asks, narrowing her eyes at the tear in the hazmat suit.

"One of the not-corpses was hanging around camp. Apparently, when you throw things at them, they absorb it and then grow. I suspect shooting them will be pointless. I did find everything I was looking for, though."