Update Event needs the option to send only to added or deleted attendees
Update Event should include a Boolean to enable an option to 'send notifications to added or deleted attendees only' that will stop notifications going out to all meeting attendees when the only property that has been modified is attendees. This is causing an issue where people are getting dozens of unnecessary notifications when a meeting owner adds or removes attendees using the API or via a connector (ex. Flow).
Though there is no control flag available, the default behavior in REST service is to send update only to modified attendees if attendee list is the only thing that changed.
Note that this requires clients to only send in parameters in the PATCH request that were actually changed i.e. the attendee list (client shouldn't be sending all properties each time in the PATCH).
Amie Gaffney commented
We are intending to use the Microsoft API and this is required functionality for our mutual customers. The workaround of sending individual invites will not scale to the volume to events and attendees which our bigger customers would have. The other option of resenting the invite to everyone is not feasible as this would result in a large notifications going out to the attendees.