How large the Royal Fleet Auxiliary needs to be

How much would the Royal Fleet Auxiliary need to grow to support the Royal Navy properly in peace and war?

A sustained four-ship logistics cycle could require twelve to fifteen auxiliaries or more overall, supporting the proposed order of magnitude of a fourfold expansion.

A roughly fourfold expansion of the Royal Fleet Auxiliary is proposed for sustained support. One replenishment ship must be with the force, another returning, another loading, and another sailing forward. Those four operational ships must come from a larger fleet that also includes vessels unavailable for service. At least twelve hulls are suggested to sustain that cycle, with fifteen or more considered possible. Counting the ship alongside the fighting force therefore understates the total fleet needed to keep supplies moving.