Email alerts with "Use global timeout"

I am not receiving any email alerts when i set “Use global timeout” as checked for individual display.

After shutting down the display, i never received any email notification. Also I get below result on using “http://localhost/Xibo/maintenance.php?key=key

Email Alerts
Tidy Logs
Done.
Tidy Stats
Done.
Wake On LAN
Done.

However, I get below result when i ticked “Use global timeout” off.
Email Alerts
A
Tidy Logs
Done.
Tidy Stats
Done.
Wake On LAN
Done.

Please make sure you’ve configured the maintenece script and email alerts as described in ‘CMS Maintenance and Email Alerts’ section of this guide - Xibo CMS Post-Installation Setup Guide