Hi,
the System Center Product Group have made an incredible effort and have implemented countless audit activities for Admin operations. You can look those up here:
SCOM gets Auditing for Admin activities and SCOM’s future after 2019 UR2
Unfortunately auditing changes related to Notifications configurations are not on the list for now.
i would certainly encourage you to post your feedback on the link Leon provided. You will get the chance to introduce your requirement directly to the Product Group and you will give others a chance to upvote a new cool feature.
Regards
Stoyan
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