https://learn.microsoft.com/en-us/windows/client-management/mdm/bitlocker-csp clearly states:
To manage BitLocker through CSP except to enable and disable it using the RequireDeviceEncryption
policy, one of the following licenses must be assigned to your users regardless of your management platform:
- Windows 10/11 Enterprise E3 or E5 (included in Microsoft 365 F3, E3, and E5).
- Windows 10/11 Enterprise A3 or A5 (included in Microsoft 365 A3 and A5).
I gather the confusion might result from the distinction between supportability of the Windows OS Editions and the license type assignment.
Btw. you should always verify the licensing requirements directly with your Microsoft account manager or Microsoft sales.
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hth
Marcin