In the language of physics, current reality is a superposition of its possible futures. The future is not a definite property of what is now. Less intuitive is the principle's time-reversal. Yet, also the reverse is true: The past is not a definite property of current reality. The current is a superposition of possible pasts. I suggest that the following is a case in point.
As mentioned before, the week before Mashiach in a sense extends to four years before its time. Its time is a function of the time of Yetziat Mitzrayim, year 1329. Now, the week before Moshiach would indeed start four years earlier if Yetziat Mitzrayim would have been in the year 1325.