I have been trying to collect all bits counting towards the completion - Propaganda posters and whatnot.
I finished the game apart from those so I just take the heli and fly to those locations.
I noticed though, after I almost finished the South / Millde of Kyrat, stuff started to re-appear. I haven't paid attention to the numbers, so I am not sure if they still count.
I thought I might be losing it and had too much whisky, so I did some of them again and later that night - they were back - even though I "Save / Closed" in between.
Is that a known bug ? I searched the forums, but it appears the only issue people are facing is getting to the unreachable posters.
Oh and that affects not just posters, but masks, journals and letters too.
Really annoying.
Even if it would count towards the totals though - given the amount of items it seems impossible to remember where you have been ...