You can manage access to Scheduled Issue in Add-ons (Security in pre 4.0.5 versions) section under System Administration section:
Use the drop-down menu hidden under the cog icon (1) to access "Add-ons" (2) option.
"Access Manager" (3) is located at the left bottom area of the page.
You can grant permissions to Project Leaders, project roles, individual users and groups.
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