Hesiod Said Posidon of Olympian Gods But Later Plato Said of Atlanteans or Titans the Difference of Sourcing

Plato circa 350 b. c. wrote that Posidon helped found Atlantis, based upon what the Egyptian priests at Sais had told the greek Solon, yet four hundred years before Plato’s day, greek Hesiod in his Theogeny wrote that Posidon was an Olympian god of Greece, not of Atlantis, so why the discrepancy? When the Ice Age was ending circa 1400 b. c., Greece was thrown into total anarchy, the ancient religion of the dominant Pelasgians lost forever, so during the “dark age” of Greece, writers such as Hesiod recorded the new religion concocted and embraced, enabled by that the story from the Egyptians about Atlantis was not yet known to the Greeks, who though were aware that the seal level has risen (when the Ice Age was ending), memorialized as the Flood of Ogyges who did live circa 1400 b. c.