Purely from a scriptural point of view?
(Revelation 7:14) "And he said to me: "These are the ones who come out of the great tribulation..."
Context - from the same discussion just a few minutes earlier -
(Revelation 2:22) "Look! I [Jesus] am about to throw her into a sickbed, and those committing adultery with her into great tribulation. . ."
J.W.'s are taught that the "unrepeatable" tribulation of Matthew 24:21 is the one described in Revelation 7:14.
Hello "brothers"!!!!! Such a tribulation was never to occur again - according to Jesus.
But if the Guardians of Doctrine in Brooklyn say differently, they must be right!
Just "wait on Jehovah". If it's wrong, it'll get corrected. :)