I tend to think of time having both chronal (time-as-we-perceive-it, "moving" forward) and quantum (potential timelines coexisting and unmoving) dimensions. Possibly even "antichronal" (with the directionality reversed, so effects can precede causes).
Someone like Trance Gemini perceives (and can possibly move through) time on a quantum level, allowing her to pick and choose which timeline she inhabits (to people without her perception, it only looks as though she's "seeing the future"). Perhaps that's how prophecy works; some people (like the mythological "backwards-aging" Merlin) might have antichronal sensitivity, and can "remember" things that are still chronally "ahead" of them. The event might be set, but the chronal "path" that leads to it can still be shifted, like switching train tracks.
Even more mundane, this could be the root of the "bad feelings" we all get just before something goes horribly wrong --a reverse memory of pain. There's a whole host of seemingly-universal experiences that we consider utterly normal (and thus have never really investigated) that could be signs of non-chronal temporal perception.