Microsoft enabled support for concurrent Microsoft Exchange Online license assignments as a new feature in Office 365, which allows tenant admins to assign more than one Exchange Online license per Azure Active Directory (AAD) user.
For more information on this feature, please visit: https://techcommunity.microsoft.com/t5/exchange-team-blog/introducing-support-for-concurrent-exchange-online-license/ba-p/3721098.
For useful software licensing information on Microsoft products, please visit: https://www.schneider.im/software/microsoft/.
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