Changes to alerts settings are tracked in two different ways: notifications and logging.
Notifications
Notifications are sent out to all alert subscribers anytime any alert setting is changed. The name of the person who changed the alert along with what alert they changed is included in the text.
Logging
If there is an open or snoozed alert and the settings for that alert are modified or the alert is turned off a audit log is associated to the alert containing all the relevant information.
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