I absolutely agree that we will not know the day or hour of His return, however, we are told to watch for His return and we're told that we will know it's growing close due to how current events will unfold. Christ mentioned this in His parable of the Fig Tree, stating that when the tree blooms, the time of the harvest is near, meaning that the time for Christ to come for His Bride is close. This is not to say that we can know the day and hour, just that we will be able to discern the general season.
Also, I would also like to point out that you raise a very, very good point in regards to the fact that God is not subject to time. I suspect, due to clues provided in Scripture stating that God knows the end from the beginning, that Time, as we know it, is actually not only finite but already completed as well. From our point of view, Time is still progressing, but from God's point of view not only does it have a beginning and an ending, it has already ended and we, presently, are merely playing out our parts in it. This theory would seem to fit with the paradoxical Scriptures which seems to state that to be absent from the body is to be present with the Lord, yet the dead in Christ rise again in the resurrection at His second coming.
It would also neatly fix the perception issue we have of free-will versus election and a few other, interesting ideas that have come out of quantum mechanics. All in all, it's an incredibly interesting subject that I'm looking forward to understanding more once this mortal finally puts on immortality and I'm given my resurrected body and all knowledge is finally made known to us.
Since God says he knows the end from the beginning, and is outside of time, he already knows who, out of his won free-will decision, has rejected him. He already knows who are his elect.