as you realize from the question you are asking "when" rev. was written would make a great deal of difference as to the meaning of the context of the book. i also in the past researched to give a more accurate date of the writing of rev.,, the more i looked at this i realized that the other books/letters in the n.t. also bear information on this. i should also add that many may view this thread and ask themselves "why would it even matter what date Revelations was written?"
so it might prove helpful to explain first to explain the reasoning for dating Revelations. that is in around July a.d.70 the temple was completely destroyed as we know so the things written then in rev. would make no sense if the temple was still standing(if written before ad70),,,and if written after ad70,,,then all of the context mentioning "the temple of god then is future tense prophecy. so it i think is an extremely important question to resolve.
as i have stated in other post about rev.1;19 john is instructed to write things he had seen,thing he was seeing and things that were to come to pass(which covers the three tenses of time past,present and future) so the book of rev. is then divided into 3 sets of time-frames. good examples of this are the letters to the 7 churches where he states the things they had done(past tense),were doing(present tense),,and the things he would have them do (future).
also in rev. 17;10 the angel states to john that "5 are fallen(past tense),,1 is(present tense) and 1 is not yet come(future tense)",,,in rev.17;8 he states "shall ascend out" so in the present tense(at the time rev. was written) the beast that was,is not yet is was then at the time of the writing of the Revelation (in the bottomless pit present tense),,and would ascend out (future tense),,,
so when makes a "world of difference" as to the understanding of the dating process of the writing of Revelations. that is if it was written before the destruction of the temple(ad70) then the statements made are a future tense prophecy of the temple and were fulfilled in ad70.,,,,but if Revelations was written after ad70 then these spoken of the temple and Jerusalem are "future tense=after ad70 another temple would come",,,
Now as for proofs of things i have found/borrowed from other researchers,,,,,when did john receive and write rev?,,,so the other letters come into play,,,i refer to them as ear-marks(pun not intended).,,,In Matthew 26;51 "one of them that was with Jesus" cut off the ear of the high priest servant(a crime punishable by death) so at the time Matthew was written,Matthew did not use peters name.
in mark 14;47,,,again "one of them" is used again not stating peters name.,,,in Luke 22;50 again "one of them",,,,so at the time all three Gospels(matt. mark luke) were written if they would have stated who cut off the servants ear this would have put peter in great danger,more than he already was as a follower of Christ.
now peter was crucified in ad67-68,,,,which means all 3 of these Gospels were most probably written before peters death because they were still protecting his identity. but then when we look at the Gospel of john,,,(john 18;10-11) john gives "Simon peters full name" as to the very one who cut off the "ear" of the servant which if peter was still alive and his(johns) Gospel would have gotten into the hands of the high priest would have been a death sentence for peter.
so in a very high probability means that at the time john wrote his Gospel(his first book) peter was already dead and it made no difference if anyone knew who it was who cut off the servants ear. so then the Gospel of john was written after ad67-68,,,then he wrote john 1,2,3,(high probability),,,"after his first book/the Gospel",,,and then his last,Revelations.,,,
so then rev. was to be given to the 7 churches in Asia so it would need time to be copied and then passed around to them. so if john wrote (four books) after ad67-68(peters death),,,,and the time frame between ad68 and July ad70 is so small 1 1/2,,then if he wrote rev. and copies were sent to the 7 churches,(via a 6 month walk) then by the time they all received the Revelations,read the book/studied it ect. then it would have been of no help if it "applied to the temple destroyed in ad70",,,,the destruction of that temple would have by then been past tense.,,,,,,,,