Switching from email authentication to OIDC Azure - dealing with users with same email address

I have read the docs on this - but I've found that when using v25.02 and despite providing the Azure UID of the user within the External Authentication ID, BookStack still complains when the user attempts to login via OIDC Azure AD that the user already exists with the same email address. The only way around this is to rename the existing user's email address to something else, let the user log in via OIDC and - as admin - delete the old user and transfer content to the newly created account.

Is there a better way of doing this?