How navies maintained hulls during wartime

How did ships receive regular work such as hull cleaning during wartime?

It was scheduled, with ships using available dry-dock stops for work such as a quick hull scrape.

Hull cleaning was scheduled during wartime. A stop at a suitable dock allowed a quick hull scrape before further operations. Prince of Wales and Repulse are offered as examples after their arrival at Singapore. Repulse is recalled as having completed the work first, or earlier, before heading toward Australia while Prince of Wales stayed longer.