Unreal Engine 4.18 Preview

Why not update ARKit plugin in 4.18p4? Where is the final offical ARKit Plugin? I mean not the Beta 0.1!
Blueprint ‘GetCurrentFrame’ output nothing at all.
And I never get Anchor object from HitTestAtScreenPosition_Tracking Space, even though ‘Existing Plane Using Extent’ selected and the result type of ‘Existing Plane Using Extent’ got.