Stewey, the idea that even the US president "knew" that there would be an attack on Pearl Harbour is just another modern conspiracy theory. Because the Americans had broken the Japanese "Purple" code, they knew that the Japanese Ambassador was to hand the Secretary of State a big message the next day, and they knew everything that was in it, and that its last part was diplomatic-speak for a declaration of war. When the President and the Secretary (Cordell Huill) were reading it over the night before, one of them said "I guess this means war", and other said "Yes, I guess so", or words pretty well to that effect. But there was absolutely nothing to suggest such an immediate opening of hostilities.
Hypognosis, the timingg confusion was that Tokyo had not told their US Ambassador why the specified handover time was so important. He thought the typed-up copy looked a bit messy, and ordered the typist to do it again. Japanese reputation in the USA has never recovered from the opportunity that his lateness for his appointment gave the President to claim truthfully that Pearl Harbour had been attacked without a declaration of war. The Japanese meant it to be legitimate, but it turned out not to be, simply because they hadn't trusted their ambassador with all the facts.