In Persona, Floor Height Offset does nothing with Auto Align Floor to Mesh disabled

In Persona, when Auto Align Floor to Mesh is disabled, Floor Height Offset has no effect on the scene.

1. Open QAGame in editor.
2. Open SK_Mannequin in Persona.
3. In the viewport, click on Show and disable Auto Align Floor to Mesh.
4. Click on Show again and adjust Floor Height Offset.

RESULT:

Nothing happens.

EXPECTED:

For the floor to move. Or if the setting isn't expected to work with Auto Align disabled, for it to be uneditable