According to SysDig documentation,
Duration: Specify the time window for evaluating the alert condition in minutes, hour, or day. The alert will be triggered if the query returns data for the specified duration.
I am afraid I do not understand what changing this value will actually do. In the example below, I am checking if a cron job has been taking over 10 minutes to execute. Will modifying "duration" change alert update frequency, i.e. the condition will be checked every 20 minutes?