It would mean that as diverse as the alternate futures we can imagine are the alternate pasts. Currently we think of the whole set of possible alternate futures as a big and rather motley set. But all of these timelines come together in an infinite number of alternate presents of which this is just one. In fact, just like there are an infinite number of timelines going from now to the big collapse, there would be an infinite number of timelines going from the Big Bang to the present. You get something that looks like two tangent paper circles.
Time moves along the axis of symmetry.
Time starts at a single Big Bang point, goes a lot of different ways and comes back together at the present or the point of tangency of the circles, then it bows out in different directions agains in different alternate futures and they come together again at the futuremost point of the continuum where the whole universe converges into a point again. This model encompasses all possible pasts and futures of this instant in time. Now take an infinite number of copies of this model for an infinite number of alternate presents. Glue them all together at the Big Bang points and the Big Collision points, and you have a model of the space-time continuum, with special reference to this present and all possible alternate presents. But other than the fact that I am writing this right now, there is nothing special about this particular point in time.