This is the best timeline of events I was able to put together. I can probably expand on it and create a separate chart to represent the theories of hand off vs book exchange, but I may save that for a different day.
https://www.youtube.com/watch?v=d3zTfXvYZ9s&t=6sI found this video to be helpful for those that are confused about how time loops works, but at this point I'm not sure what the ratio is of discussion:trolling. IMO we're similar (if not identical) to Harry Potter's time loop. I think both options of single handoff vs book exchange are valid, but I lean more towards the latter as we never see any previous parts of the loop. They left the story very open ended and you have to make a lot of guess work and assumptions. If the book exchange happens in every timeline, I think wherever the AI winds up is pretty pivotal and I wish they weren't vague about exactly where on alternate timelines they searched. The story is full of half truths which makes it difficult.