
Plan for migration to Apps and Books in Apple Business Manager
To get started migrating, Content Managers with Volume Purchase Program (VPP) accounts must migrate their licenses to a location in Apps and Books. For the best migration experience, organizations should map each purchaser to a unique location to ensure that all licenses (assigned and unassigned) are automatically moved during the initial migration. It’s recommended that you move all Content Managers at the same time. This can be done by each Content Manager, or by an administrator with access to all accounts.
For more information, see the Apple Support article Invite Volume Purchase Program (VPP) Purchasers to Apple Business Manager.

After migration, licenses are associated with the location they migrated to rather than with the purchaser’s legacy token. If a Content Manager migrates to a location that already has licenses in it, only their unassigned licenses are moved to the location during initial migration. (This process avoids any disruption to license assignments in mobile device management (MDM).) Assigned licenses remain associated with the purchaser’s legacy token. After these licenses are unassigned in MDM, they can be moved to a location in the Apps and Books section of Settings.
If a Content Manager account has VPP credit associated with it, the credit remains associated with that purchaser. VPP credit isn’t transferred to the chosen location. See Buy VPP credit.