Why older armoured cruisers would stay in service

Which older British armored cruisers would enter reserve after a sixteen-gun 9.2-inch cruiser appeared?

None immediately; continued cruiser demand would delay retirement until newer Town-class ships arrived in numbers.

No older class would enter reserve immediately when the hypothetical sixteen-gun cruiser appeared. The existing armoured cruisers are described as too young for immediate retirement, and Britain still needs many cruisers. Increasing numbers of Town-class ships would eventually create room to move older vessels into reserve. A more powerful design alone would not remove the demand for the existing hulls.