to see the future you must observe time from outside space/time gravitational force.

since time/space is fluid at the eyes of the observer will look different every time is under observation

so generally you can observe major events, those that appear to happen most of the time you observe and also see how those events gravitate in a period of time. This period could be exended to months or years.

so you can guess that there is quite a lot of possibility that a major even created by many forces to happen around a date (wich is just counting time...inside the time)

that's why nobody can give exact time

when an event is given with exact date that turn to be right it has been observed from inside the timeline and probably directly enginereed.