Colonization begins within 24 to 48 hours once drywall reaches 20 percent moisture content

https://storage.googleapis.com/colorado-springs-co-water-damage-restoration-express/water-damage-restoration-colorado-springs-co/colorado-springs-co-water-damage-restoration-express-delivers-certified-carpet.html

No, drywall should not get wet at all—even minor moisture exposure poses a serious mold risk. Documented research shows that mold colonization begins within 24 to 48 hours once drywall moisture content reaches 20 percent, well below saturation