Set-MSOLUserLicense & STANDARDWOFFPACK_FACULTY - license invalid

Trying to bulk-assign licenses to our "Office 365 Education for Faculty" subscription - the SKUID of which is STANDARDWOFFPACK_FACULTY (see below) - this is failing though - message below. Is this  not possible with this SKUID ??

PS C:\ian> Get-MsolAccountSku

AccountSkuId                      ActiveUnits WarningUnits ConsumedUnits
------------                      ----------- ------------ -------------
domain:OFFICESUBSCRIPTION_FACULTY 0           720          9
domain:STANDARDWOFFPACK_FACULTY   500720      0            755
domain:POWERAPPS_INDIVIDUAL_USER  10000       0            6
domain:PLANNERSTANDALONE          300000      0            3
domain:POWER_BI_STANDARD          1000000     0            29

PS C:\ian> Set-Msoluserlicense -UserPrincipalName user@domain.com -Addlicenses "domain:STANDARDWOFFPACK_FACULTY"
Set-Msoluserlicense : Unable to assign this license because it is invalid. Use the Get-MsolAccountSku cmdlet to retrieve a list of valid licenses.
At line:1 char:1
+ Set-Msoluserlicense -UserPrincipalName user@domain.com -Addlicen ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : OperationStopped: (:) [Set-MsolUserLicense], MicrosoftOnlineException
    + FullyQualifiedErrorId : Microsoft.Online.Administration.Automation.InvalidUserLicenseException,Microsoft.Online.Administration.Automation.SetUserLicense