Listen to his most recent speech. Hmm… Lots of "probably"s in that speech! I don’t recall him using “probably” very often before May 21. It’ll be interesting to hear what he says after October 21.
That’s something that’s covered in week 1 of the Prophesy class: never give a firm date. He must have been asleep in class or absent that day.
Family Radio - a Non-Prophet Organization
Also, giving a date so far into the future as to be meaningless should work. The Messiah shall coming to earth in July of 3135.
Avoid specific predictions, obfuscate, and make extensive use of blank verse.