Scheduling and managing events using Outlook.com calendar
I'm not getting duplicates in my tests, we not from proper outlook meeting updates.. Outlook desktop properly changed the time (sending from gsuite account to exchange mailbox).
Gmail web is a problem - the meeting time did not update The attached ics file has the correct time. Opening and accepting it would result in duplicates as it won't remove the old one.
I test both changing just the time/date and change the subject, time and date.