RE: In short, any alleged post-apostolic prophet needs a verifiable 1.000 batting average in regards to predictions AND Christology, or he’s a false prophet.
OK, just for argument’s sake, what do we make of the NON-FULFILLMENT of Jonah’s prophecy to the Ninevites?
This is what he said : “Forty more days and Nineveh will be overturned.” (Jonah 3:4).
That’s it. NO CONDITIONS, NO IFs or BUTs. Not even an exhortation to repent.
Personally, I'd say that the sweeping nation-wide changes in Ninevah, from the greatest to the least (Jonah 3:5-10) constitute a definitive moral overturning.