I know that the source of the magic is important but I'm surprised how no one is mentioning how the healing spells of AST is implied to use some sort of time magic.
As in how the npcs mention that it is as if they were never hurt in the first place. It's a little ambiguous so maybe rather than saying they reversed time, it makes more sense that they changed the fate of that individual to be less hurt.

I think that's the most interesting dynamic of AST healing since it's very different than the other healers.