The Exchange team has worked with the Windows team to isolate the source of the problem.
An update for Windows Server 2016 will be made available to resolve this issue.
If you are using Public Folders (legacy or Modern) and would like to migrate some of them to Office 365 Groups, we are working on a solution for that.
We are starting with the migration of Calendar folders and will move on to other types as we complete work on calendars.
We would like to have customers who would like to try this migration to provide feedback.
Please email us with below information if interested.