Should have added:
If Jesus himself said that no one knows but the Father, who am I to say I do know? Or who is anybody else?
So apparently, Jesus believes that those in Him would know not the exact time of His return, but based on the signs that He gave for the Tribulation coming to pass, which are happening now, we would know that His return for His Church is very near.
And, Jesus also commands us to watch for His return. So it is possible to know when the Rapture, which is a signless event, is very close to occurring.