The Japanese Naval Command has asked for reforms to their destroyer fleet; thus a new requirement has been submitted for all new Destroyer Production. They will be required to include a Depth Charge Rack on the stern, mine bays in the bottom of the hull (that can be opened to drop mines, these hull spaces will be built with bilge pumps to avoid causing sinking), and additional torpedo racks. All three of these being specifically for countering Submarines which is the primary goal of our Destroyer Fleet anyway. The Torpedoes take precedence over the Depth charges as they are simply more important than them as Torpedoes and be aimed, depth charges cannot. However, they still have their uses which is why we will include at least 2-3 of them on each ship. Mines will also be less prioritized but still more so than the depth charges as we can set the mines to be a constant barrier against Subs. All ships will also have more Anti-air, the war against Oceania has taught us that Anti-Air is vital and can't be ignored by any means. All of this will be alongside the standard cannons on each Destroyer and Ship.
Aircraft Carriers will also be built with drone pods in the deck and hull that are completely invisible until they open up and drones are released.