Exchange 2016 cu3.
In the past I was able to delete mail/mailboxes and it would create white space within my database.
I would check my white space with the follow power shell command.
Get-MailboxDatabase "datebasename" -Status | fl Name,AvailableNewMailboxSpace
Recently when deleted about 10GB of mailboxes the white space never showed up and my database continues to grow.
The Mailbox database limits are set to 0 for keep deleted items and mailboxes. Also, the default retention setting are set for each mailbox.
Does anyone know what else I can check or why my whitespace isn't freeing up?