Noah did not know.
Matthew 24:37-39 is not saying that Noah knew the day that the calamity would begin. It is speaking to the people who were "marrying and giving in marriage", those worth of the destruction. Noah was him that was set apart.
I would also point out that Jesus never contradicted Scripture and the prophets. The text is clear that no man will know the day or hour. Christ is giving an analogy to further emphasise the point.
I think you are missing the underlying point which is that, as with a traditional Hebrew wedding, no one knows the date or hour … until the Father of the Bridegroom calls it. There is no prohibition against speculating or anticipating, just a warning to be ready when he calls. If this were not so the Noah and his family would not have been in the Ark when the rain began falling but with those who were banging on the door once they saw the waters rising. Likewise if no one is paying attention to the Word (the oil in their lamps) then the day will overtake them as a thief in the night.
My point is that if no one can know the day or hour, then speculating about the day and hour is an exercise in futility.
Is it said in the Scriptures that Noah knew the day ahead of time?
The fact that he and all his family and all the animals were onboard ready for Yahuah to close the door is confirmation that he heard and obeyed the call when it came.
Also the 5 wise virgins were ready and heard the call - did they never sleep or do anything else, no they were awake at the right time and had oil in their lamps.
"NUN. Thy word is a lamp unto my feet, and a light unto my path." PSALMS 119:105 KJV
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