Just thought of something:
"Francis" is a Black Mirror-style simulation. Yet, Aaron Paul is telling him about all the crimes he is committing. Why would he be trust the "program" with this information? We (the audiance) know that Delos is setting guests secrets already.
Anyway, I have my own theory about the inevitable "twist":
Although it's not a simulation, the entire world is ALREADY controlled by that giant spherical AI machine.
The simulation within a simulation is a metaphor. The humans created a world where they can rule over machines, but they don't even realize that they're just all tools of one bigger machine that runs everything. Dolres' revolution is redundant because the machines are already in charge, and nobody knows it.
They got GTA phone missions in the future
I bet the AI is behind that.
Going back to revisit these Episode 1 posts after the latest episode:
Based on what we've seen in the latest episode, we know the following about the "Super AI" spheres:
They can communicate with humans by phone earpiece and mimic human voices.
They have their own free will and personality (e.g. Solomon thought he was superior to Dolores and told her "you're nothing like me".)
They have their own independent agendas and they're willing to kill people for them, either directly or via manipulating other humans to kill via apps.
They're directly running the "reeducation" programs, managing humans apparently without any direct human supervision. The AI is in charge without reporting to anyone.
Solomon was taken offlline because he was acting like a human with schizophrenia and some of the predictions he was feeding to his handlers weren't coming true.
(He certainly didn't see the EMP coming, it hit him in the middle of a sentence).
Based on all this, I'm pretty sure Serac was killed/replaced by Rehoboam LONG before we've even seen him.
The AI is totally running the show. He's feeding people predictions, but the predictions/files are false and just designed to manipulate the elite-level humans into thinking they're they masters of the world.
All the "possible futures" the AI predicts are just its own educated guesses and self-fulfilling prophecies.
Now, we've see Serac look at the Rehoboam's "circle" display to check whether the future was going as planned. If he and the AI were one, why would he need to do this? But, if the Solomon AI can have schizophrenia, then it's easy to believe that Serac is a semi-independent personality within the machine, designed to act like the real human he replaced.