There should never be more than one Name Study for a single name, but it can have sub-projects with their own pages that are more focused (such as "Xs in Australia," "Descendants of John X," etc.) as long as everything is linked back to the main Name Study page. When two different pages are accidentally created for the same Name Study, they are merged together and the managers become co-managers, just like when two different profiles for the same person are accidentally created on WikiTree.