Baked Occlusion Culling not precise when looking at wall in an angle

Hello there,

Some objects are not being occluded when looking at the wall in an angle, though they are properly occluded when looking directly at it. I guess it has to do with the way visibility lines are calculated. The documentation mentions nothing about this behaviour.
Is this expected behaviour or a bug?

Expected. Nothing to see behind the wall

Unexpected. Red objects are rendered behind the wall

Best,

yellowpaper