Q&A: how long would Repulse's reconstruction take?

How long would Repulse have been out of service for a Renown-style reconstruction, and how useful would the rebuilt ship have been?

About eighteen months, and a second ship with Renown's capabilities would have been extremely useful, but taking Repulse out of service competed with urgent fleet requirements.

A Renown-style reconstruction would have transformed Repulse's machinery, protection, anti-aircraft battery, and fire control, though it required a long absence from the fleet. The estimate is roughly another eighteen months out of service, and a second fully reconstructed sister would have been extremely useful. Replacing Royal Oak in the reconstruction queue might have been defensible in hindsight, while postponing the Queen Elizabeth-class work would have weakened the Mediterranean answer to the Italian fleet. Modernisation priorities were constrained by theatre requirements and ship availability as well as money and technical possibility.