Users imported from Jira Service Management projects have standard user role instead of reporters

I was trying to create a helpdesk project with data migrated from jira service management, the issues got migrated successfully, however hundreds of users who created issue got added as standard registered users that have access to the youtrack dashboard instead of reporters, and there are no way to bulk change their roles. I'm worried that will the imported users receive any email about their role updates I made? Is this expected and is there a way to revert this or bulk change them to reporters? Is reporter role counted in user quota?

Many thanks.