it does not need to be dry for bubble hash, iso hash, green dragon or butter.
It really only affects your potency, 1 oz of dry matter is way more than 1 oz of wet matter. Dry material is also harder to filter, and some say green material gives your hash a slightly better flavor.
Trim goes into a zip lock, and straight in the freezer - once I decide to make something, it goes straight into the project with no drying at all.