What patrol boats? When were these modifications made? What's the range and speed of these patrol boats by the way. It's not at all clear to me how these liners are going to carry all those landing barges and how they are going to be launched. Also a quick check showed the speed of the liners listed as 21 knots. If that was there max speed when new do they still make 21 knots? Indeed for the length of run you are assuming can they keep up the speeds required? Which means that they will be picked up by radar well before things are shutting down. Time enough to figure out that they aren't B-17 and alert the defenses. If the alert is given as much as half an hour before the planes show up the chance that subs or planes will inflict much in the way of damage before an engagement occurs is pretty minimall. Maybe for a little while. But the IJN had the same faulty escort doctrine that just about everybody had early in the war. This will leave the spotter and its escorts very vulnerable. And of course escorts don't help much vs AA either. One of the problems here is that they could be spotted and not know about it or even if they did know about it what would they do. Say radio Honolulu goes off the air 30 minutes out for the first wave. What do they do? Historically they were going to cancel the second wave. Now however you've got the battle line hanging in the wind. And in the mean time the British have time to secure Singapore POW and company arive safely there as well. The Dutch have time to prep the oil fields and refineries for a through demolition and also shore up their defences.