Where displaced four-inch guns could go

What would happen to the four-inch and five-inch weapons displaced by a standardized 4.7-inch programme?

Existing four-inch weapons could move to trawlers and other auxiliary craft, while the failed five-inch system and the superseded 4.5-inch programme would not create comparable stocks.

Surplus four-inch guns could remain useful on trawlers and other small wartime craft. The counterfactual does not produce a similar pool of 4.5-inch weapons because that programme is displaced by the 4.7-inch development choice. The British five-inch effort had failed and therefore also offers little usable stock. Standardization on frontline ships could coexist with older calibres in secondary service.