Oh yes, him! (I was in his cave on Patmos 3 years ago. Awesome.)
He experienced wonders in heaven above, and signs in the earth beneath; blood, and fire,
and vapour of smoke: the sun was turned into darkness, and the moon into blood ...
... but I can't seem to remember exactly when he saw all of this!
That is because you have not done the work to understand the whole book.
If you are a Preterist which seems to me that you are or at least are leaning in that direction, teach that the Book of Revelation is primarily a prophecy about the Roman war against the Jews in Israel that began in a.d. 67 and ended with the destruction of the Temple in a.d. 70.
In order for Revelation to be a prediction of the future (Rev. 1:1, 3, 11, 19; 22:6-10, 16, 18-20) and if it was fulfilled by August a.d. 70, then it had to have been written by a.d. 65 or 66 for the Preterist interpretation to even be a possibility. There is absolutely no other way for the Preterist view to be acceptable except the Revelation be before 70 A.D.
If you have not read any information from the leading Preterist Ken Gentry, he personally has noted this major weakness when he said of fellow early date advocate David Chilton, " if it could be demonstrated that Revelation were written 25 years after the Fall of Jerusalem, Chilton's entire labor would go up in smoke."
Actually, all one would have to do is to show that Revelation was written
any time after the destruction of Jerusalem on 70 A.D.
The futurists interpretation is not dependant upon the date of Revelation since it does not matter when these events take place since they are still future to our own time. However, the date of Revelation is essential to the preterist position and explains why they are so focused upon defending an early date.
Today, the overwhelming consensus of scholarship believes that Revelation was written well after a.d. 70. Most have concluded that Revelation was written around a.d. 95, primarily because of the statement by early church father Irenaeus (a.d. 120-202) around a.d. 180.
Now that is a fact which anyone who wants to know and can do the work and confirm for themselves.
It is important to note that Irenaeus was from Asia Minor (modern Turkey). The Apostle John was also from Ephesus in Asia Minor. Irenaeus was discipled in the faith by Polycarp who was discipled by the Apostle John. Thus, there is a direct link between the one who wrote Revelation and Irenaeus. This strongly supports the credibility of Irenaeus and his statement.
It appears logical that if the theory teaching an earlier date of Revelation were genuine, then it should have had a witness to it in Asia Minor and would have begun earlier than the fifth and sixth centuries. If the early date were really true, then it would have had a 30-year head start to establish itself within early church tradition. However, that is not what happened. Such reality argues against the early date view and is a strong support for the late date view.
So then the answer to your comment of..........
"but I can't seem to remember exactly when he saw all of this";
is in a vision from God in 995-96 A.D.