I wonder if the Marines will be working in conjunction with the radar in Hawaii, which is ahead of where it was OTL. If the Marine air units catch the Japanese first wave further out from Hawaii, no matter what this is going to be a big plus for the US. There will be inevitable disruption of attack formations over and above those aircraft shot down or too badly damaged to make their attack runs, so fewer aircraft over Pearl than OTL. Every minute of warning PH and the other military bases gets means watertight doors can be closed, battle stations manned, and ships can begin to get steam up. On land some fighters will get off. AA emplacements will be manned and with ammo compared with OTL, and folks will be in trenches rather than in barracks. All of this adds up to less damage for the US, and more losses for the Japanese and this is only for the first wave. The second wave is going to be hit harder and do less damage also.
If the Japanese are encountered 50+ miles out, this means perhaps 15 minutes extra warning for PH as a whole. Of course if encountered a little further out more time. At least for the ships at Pearl, I can't imagine that they can't get closed up at GQ, condition Z set throughout the ship, and batteries manned and loaded with 15 minutes warning.
Those aircraft headed for Ewa are going to be in for a world of hurt - wonder if any other fighters can get off on 15-20 minutes notice.
And all this makes it crazier when you know that Yamamoto ordered the attack to continue even if they were discovered 24 hours in advance.