In the Haggada, there's a song at the very end that says:
קרב יום אשר הוא לא יום ולא לילה Near is the day that is neither day nor night
the gematria of the blue letters are תשס"ח 5768
In Zechariah 12:3. It says:
וְהָיָה בַיּוֹם-הַהוּא אָשִׂים אֶת-יְרוּשָׁלִַם אֶבֶן מַעֲמָסָה, לְכָל-הָעַמִּים... And it shall come to pass in that day, that I will make Jerusalem a stone of burden for all the peoples
The gematria of the bold large words is (תשס"ט (5769 and the end acronym of the three words is אמת (truth).
Rav Elya Svei Shlita, Rosh Yeshiva of Philadelphia, said the following, "In תרצ"ט, 1939, Rav Elchanan Wasserman, zs'kl, said that Moshiach would come in 70 years."
Another story related to Rav Elchanan Wasserman that he was with the Chofetz Chaim at the beginning of World War I (1914) and the Chofetz Chaim said that WWI was the first of three Gog Umagog wars. The next war would be in 25 years. That story ends there, but clearly Rav Elchanan Wasserman was someone in the know.