How County-class cruisers would move into second-line duties

Would County-class heavy cruisers be due for replacement by the middle or late 1940s?

They would probably shift into second-line duties while newer heavy cruisers assumed the leading role.

By the middle or late 1940s, the County-class cruisers would be aging relative to a new generation of heavy cruisers. New ships would take the leading heavy-cruiser assignments, while the Counties moved toward the lower-category and second-line work previously performed by older C- and D-class cruisers. This would be a gradual force-structure transition rather than immediate disposal, allowing a successful class to remain useful after losing its place at the front of the fleet.