Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
The update automatically changed ALL of my default displays to Aptos 12 points and stopped loading my Normal and Excel start-up templates.
All of my Draft Outlook emails that previously used multiple fonts and are now unusable.
I don't know why draft messages would be affected by format changes. This may very well be a bug. Report it using the feedback facility in your version of Outlook.
You may want to post a question in the Outlook forum as well; go to https://answers.microsoft.com/en-us/outlook_com/forum?sort=LastReplyDate&dir=Desc&tab=All.