Hi @Vincent Ferranti ,
Welcome to our forum!
I checked the Outlook settings for default reminder times, but that setting is only for meetings that the current user creates and sends out.
As Jade Liang-MSFT mentioned in this thread, you can check how the default reminder works:
is there any script or batch file she can run in where ALL meetings are set to a specific time?
If you need the help of script, we will add "Office Development" tag.
Hope to help you!
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