Early US 16-inch guns accelerate the battleship race

How much changes if the US Navy adopts 16-inch guns with the Pennsylvania class?

It accelerates the international gun race and likely brings British 16.5-inch battleships into the program much earlier.

Adopting 16-inch guns for Pennsylvania would follow two American classes armed with 14-inch guns and bring a larger caliber into service earlier. British planners would hear about the change while considering their own battleship programs. A 16.5-inch British design is suggested as a possible response, potentially even replacing the 15-inch choice for Queen Elizabeth. Revenge might retain 15-inch guns, but larger British weapons would probably follow quickly. In this counterfactual, the resulting competition also prevents the anticipated building holiday.