$BitLocker = Get-BitLockerVolume -MountPoint $env:SystemDrive
$RecoveryProtector = $BitLocker.KeyProtector | Where-Object { $_.KeyProtectorType -eq 'RecoveryPassword' }

Backup-BitLockerKeyProtector -MountPoint $env:SystemDrive -KeyProtectorId $RecoveryProtector.KeyProtectorID
BackupToAAD-BitLockerKeyProtector -MountPoint $env:SystemDrive -KeyProtectorId $RecoveryProtector.KeyProtectorID