Yes indeed, that is a decent template there you had already posted earlier.
That is probably good idea, to be reoccurring a few times can be good for important warning/alert.
This seems like sort of unusual phrasing for this kind of alert, not sure when/if email change would be an “error.” Depending on the level of suspiciousness of the change more urgency in the alert can be good, like **Suspicious email change alert!!!** Please contact us right away if this is not recognized!" Also phone alerts can be good and/or automated temporary account suspension if admins want to be super fancy.