Change In Visibility

[Warmonger]

See attached save file.

A Unit View for the unit in hex 49,24 shows an intermittent pattern of hexes (every third hex) to the SE. All visible hexes there are level 0, clear. The hexes around the visible hexes are also level 0, clear. So why aren't they visible as well? There was no action in that part of the map so there shouldn't be any micro-smoke affecting visibility.