When renaming an index there are a few things to consider. These are highlighted in the warning message that appears when renaming an index from the Dashboard.
These relate to the following
Access: If this application has API keys or collaborators relying on index restrictions, they might need to be updated in order to maintain access
Within Team Member permissions, it's possible to restrict which indices users have access to, for example, you may declare dev_*, staging_* to grant a user access to all indices with a common prefix. Therefore, if you change the name of an index that you have specified a user has access to, you will need to ensure you update the name in the user's index permission settings.
Analytics: Analytics data attached to this index name will no longer be accessible from the Algolia Dashboard.
Analytics data is tied to an index by its name. As a result, renaming an index will dissociate it from its old analytics data and the data will not be accessible under its new name.