Hi @RG
Welcome to our forum!
Based on my research, you can use conditional formatting to meet your requirements. A visual refresh of the calendar based on certain criteria. For example, you can create a rule to highlight or color-code events where the Show On field is set to Tentative. This way, you can easily discover new appointments made by your manager.
You can refer to the steps below:
In the calendar view > click View tab > View Settings > Conditional formatting > Add a rule to automatically categorize the events on your calendar. More information, see: Use conditional formatting to give your calendar a visual refresh - Microsoft Support.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.