If the carriers were at Pearl Harbor and the battle line was at sea

What changes if American carriers are at Pearl Harbor on 7 December 1941 while the battleships exercise at sea?

Japan gains a stronger short-term advantage, but it must still find the battle line and cannot eliminate America's surviving carriers, reserves, or industrial replacement power.

Japan would be pleased to find two American carriers in harbor because their loss would reduce the immediate threat of counterstrikes. The battle line at sea would remain dangerous only if Japanese forces could locate it before it regrouped with Yorktown, Saratoga, and fighter cover. The United States still had a fleet too large to remove in one raid and a construction base able to replace losses. Japan, by contrast, needed early local superiority because it could not replenish carriers on the same schedule.