As the title says - if a damaged moving train comes in for example, or when a wall on the edge of the turret's area is damaged, sometimes the repair doesn't fully work - or 'stops working'. Even when I put a turret right next to it (after the prior occurs) the instance isn't repaired anymore and I have to do it manually.
I don't know how to explain better haha.
edit: If I read the changelog it seems the edge thing might be fixed (not sure if I updated the mods the last 2 days), will keep you posted if it's still broken