This is why (way back, in our long-ago convos) I said that this is why I do not believe this verse is "an idiom" [or whatever] speaking of "the Feast of Trumpets" / Rosh Hashana (as indicating "rapture timing").
IOW, I do not believe Jesus "intentionally inserted" a comment about "our Rapture" into a CONTEXT which wasn't ABOUT that at all.
He's referring to His Second Coming to the earth, here (in this verse), IOW.
If verse 36 is not indicating the F of T's, then what is it supposed to illustrate?
Another thought: it is a simple matter for mere men to ascertain the day of the F of T's by simple observation.
God need not keep secret something that anyone can tell.
But the rapture? That is altogether a matter of the UTMOST secrecy, and is in effect God's trump card. Only after the rapture can Satan react. And Satan DOES react, rapidly, vigorously, and violently.