Update calendar invite without sending 'meeting has been updated message' to attendees

ssoutrs Hi, if using Outlook on the web the updates won't be sent to all attendees as it has a built-in behavior when it comes to these notifications 

Send updates options for attendees not shown - Exchange | Microsoft Docs

If using the Outlook client she should save the updated info (File - Save) and not use "Send update" button. If adding/deleting someone in the invite make sure to select the proper option at the prompt.