I have a question regarding licenses:

Let's take an example. Let's take we have an EmailXtender with 200 mailbox licenses, and all the licenses are being used since there are 200 user mailboxes in the Exchange. If we delete few mailboxes in the Exchange, while the already archived mails for those should still be available via EmailXtender, will the licenses used for archiving those mailboxes be freed for the new mailboxes?