This is also something I have run into during my work as Backstory Leader. My team works by dividing the Houses amongst them and searching on the Marauders' Map user list for them by House, then checking backstory, name and profile text.
Unsorted people fall between the cracks, as there is no way to sort the user list unless by House, thus, it's hard to find them when they joined ages ago. Now of course, we can't sort someone to a random House without them finishing the Sorting Hat quiz, but perhaps it would be a possibility to search the user list for them. Simply add the category 'Unsorted' to the user list under House, and we would easily be able to find them and check them.
Additionally, when editing an illegal name for an Unsorted person, not automatically place them into a House when saving 'edit user' but keep them as Unsorted. This way, if they return to the site, they can still finish the Sorting themselves.
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