Why number of “Non-user mailbox” protected by Collaboration Protection exceeds the purchased license size?

Issue:

Why number of "Non-user mailbox" protected by Elements Collaboration Protection exceeds the purchased license size?

Resolution:

Non-user mailboxes will not be counted directly to the license size, like 1 license: 1 mailbox. Instead, it will be be counted with a ratio of 1:2.

For example if you have an Elements Collaboration Protection subscription that includes 5 licenses, the maximum amount of mailboxes that you can protect is 5 user mailboxes and 10 non-user mailboxes.

Please take note that shared mailbox is considered a non-user mailbox.