The cited sk states the following:
To perform an automatic update of Trusted CAs on Security Gateway:
Note: This option is available starting in SmartDashboard R75.40.
...
This option is selected by default. Updates for the trusted CA list and Blacklist are automatically downloaded to the Security Gateway. You are notified if there is an available update. If you clear this checkbox, you disable the automatic updates.
So it is not clear to me why you do ask that at all !
CCSP - CCSE / CCTE / CTPS / CCME / CCSM Elite / SMB Specialist