Now..., when was the book of Revelation written?
And when does Jesus come again, according to what he told the disciples?
It says it right on the first page. Oh, I forgot, the futurist date is the one set by the magisterium of the church.
That I can tell you in one word: tradition! (Tevye in Fiddler on the Roof)
Repeat after me Tradition, tradition! Tradition! Tradition, tradition! Tradition!
And when does Jesus come again, according to what he told the disciples?
Sometime in the future, we know not when. "But of that day and hour no one knows, not even the angels of heaven, but My Father only."