Active IQ Unified Manager (AIQUM) 9.6+
When an ONTAP cluster monitored by Unified Manager (UM) is upgraded, on the next inventory collection it is assigned a new internal UUID in the UM database. With this new UUID the cluster is considered new to some UM processes, and UM will begin the subscription process for the automatically-subscribed EMS messages appropriate for that ONTAP version.
Note: Even though the cluster is considered new to UM after the upgrade, historical data will still be intact and there should be no noticeable effect to the user.
For more information, review the list of EMS events that are added automatically to Unified Manager.