Adding PIM enabled security group to an Access Package

This isn't controlled by a tenant-level preview setting. If your group is already PIM-enabled and you've met the documented prerequisites, the additional Eligible member and Eligible owner options should appear automatically.

If you're only seeing Member and Owner, it's most likely because the feature hasn't been enabled for your tenant yet. Since it's a preview feature, Microsoft is rolling it out gradually, and not all tenants receive preview capabilities at the same time, even if they have the required licenses.

There isn't a manual switch under Entra > Identity > Settings > Preview features to enable this functionality. At this point, the only thing you can do is wait for the rollout to reach your tenant or open a Microsoft support case to verify whether the preview has been enabled for your tenant.

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