Update (4/12/23): This feature was enabled in our worldwide and 21Vianet clouds in November 2022. All tenants in these clouds will see the changes. Rollout to our GCCH and DoD clouds has been paused ...
Updated Apr 12, 2023
Version 11.0
Blog Post
MSFrodo
As I understand it the change will happen. And this command will no longer work;
Get-EXOCASMailbox -filter 'name -like "a*"'
To be honest we use this in our MIM agent, but could be in a script as well.
It is not the only command that is run. We also run Get-RemoteMailbox with the same filter. And can then match the result together. Because we have more than 60 000 mailboxes we can't really run Get-EXOCASMailbox in an foreach against the result in the Get-RemoteMailbox. It take many more hours than run them separately. And your suggestion in using DisplayName is not possible because that is not unique.
If you started to support query for alias with Get-EXOCASMailbox that could be a solution. But as of now I can't really see that you give us any working option.