This key item's description: "This painting of a sacred tree is thought to have been finished around Crystal Era 480..."
Palomel's comment on this key item: "You're telling me that a random p-p-peddler claims this to be a four-hundred-eighty-year-old painting?"

That implies it's currently 960 C.E., when every other quest and mission uses a presumption of 884 C.E. Unless the presumed year for lore advanced ~80 years, one of these is in error.