Why wartime fleets still rotate in thirds

Did wartime navies abandon the peacetime rule of rotating ships through deployed, training, and maintenance states?

They pushed availability harder, but the practical cycle still worked out to roughly thirds because ships and crews still needed preparation and maintenance.

Wartime urgency pushes more ships into active service. Readiness still cannot be sustained by treating every hull as permanently deployable. A rough thirds cycle leaves one part of the force operating, another preparing, and another undergoing repair or maintenance. The exact proportions can tighten, but the underlying demands do not disappear.