Rly? How long ago did we pass this event horizon? Millions of years?
Not that kind of event horizon. We're not the ones moving here, and neither is any other point of reference in the universe. It's just that other points of reference seem to move further from us because the amount of space between them increases due to some currently unknown reason (speculated to be dark energy, cosmological constant or dragons).
The one Battuta refers to is the distance where the expansion rate of the universe exceeds velocity of light in vacuum (ie. between point P and us, space is generated at a rate large enough to prevent photons from point P to ever get any closer to us). That's the cosmological event horizon and, if current data is accurate and the expansion is accelerating, is only going to come closer and closer to us.
Of course, because of simultaneity problems with photons, our observations have a lot of lag, and we are actually observing photons that started their journey from point P relatively soon after the Big Bang. We will be able to continue observations of these early objects up until certain threshold where their radiation basically red shifts to blend into the cosmic background radiation. If we could keep our instruments fixed on a certain target about to pass "beyond" the event horizon, we would simply observe the wavelength of those photons to approach infinite, until we wouldn't receive any new photons from it at all from it.