That would be accepting that time is actually linear in the first place. That's one of the fun-but-frustrating things about time travel fiction. Time can be seen as a dimension of space, so is time really "moving" and "linear" or is that how we perceive it? Sounds aren't really sounds, they're just the way our brain interprets vibrations in the air to give us an advantage in our common material surroundings. Color isn't really color, it's just the way our brain interprets electromagnetic radiation around the same wavelenth as our sun's peak to give us an advantage in our common material surroundings... etc. Time could be anything.
For that matter, if you were able to comprehend everything that has ever happened, you would be able to predict everything that will ever be. Ultimately, there's probably no such thing as free will or choice, just an endless stream of cause and effect whose seemingly infinite and miniscule variables of influence will never be comprehended by an individual, thus giving us the illusion that we're making decisions when in reality it's just testing our hardware.
Put those together and you might basically argue that all time is happening at once, everything contained in the timestream is already decided, and the nature of the medium is both fluid and (in an extra-three-dimensional sense) traversable, allowing closed loops and visitations that don't affect the overall nature of it. Perhaps it was even created this way by extradimensional beings, thus instilling an innate mechanism of destiny.
LONG STORY SHORT: When dealing with time travel, unless the fictional medium makes radically obvious paradoxical mistakes, it's best to just take it at face value as "functional."
The only thing holding me back from a cushy future of translating the Japanese language is a crippling inability to read the Japanese language.
I'd be like the Overly Attached Girlfriend of the lore team's meetings.
"Don't... don't you have some localizing to do?"
"Oh, no, I stayed here after you went home and wrapped that up already. I've got nothing but time to listen. You want me to leave? ... But then who would give you the antidote to what I put in the coffee maker a few hours ag- YOU CAN HAVE IT AFTER THE MEETING. Jeez. Touchy."