Do you see the Triumph as being something instantaneous, as such, that can be pinned down to a particular date? I have always thought of it as more of a gradual thing, or at least something that would be spread out over time to some extent, such as a series of momentous events, perhaps.
I wouldn't disagree, but I think it might be punctuated with some very specific events, and maybe a momentous ending, in which the period of peace is granted to the world in some grand way. Isn't the quote: "In the end, my immaculate heart will triumph, and a certain period of peace will be granted to the world." ...? Maybe i am quoting a paraphrased version or something not accurate. But for some reason I got the sense after studying Fatima and Garabandal that there was something definitive at the end of the Chastisements.
I think we learn from Akita and the prophecies of Elena Aiello,..the era of peace will be preceded by the purification through fire during the three days darkness