Odd Outlook Invite Behavior - Invite Update Notifications Not Sent to Attendee In-Box

SME, I have noticed a new behavior in Outlook desktop app. My company is using Office365. I updated a meeting invite with a message to ask attendees to attend. We kept the meeting on the calendar, and use it as needed. None of the attendees received the invite notification with the updated message. I have delegate access to my manager's calendar. I save all his invites to a folder, when I checked there was no notification. I checked my deleted folder and again no notice. Three of my colleagues confirmed they did not receive the notice, but the invite is updated with my message.

Has something changed on the Outlook invites? I saw a video of how to send "silent" updates. This was like 4 steps, and I clearly did not take this route, especially since I did not even know it was possible. I can see how this might be helpful in the future. But not for the scenario I presented above. Thank you for your expert advice.