Uncharted 4 Story 'Changed 100%' After New Directors Came OnI'd presumed this was the case. They'll have been working on it for over 2 years which is by far enough to completely re-do the story and make it Naughty Dog quality. All the previous Uncharted games have had 2 year dev cycles haven't they?
Finally have our answer. The story was 100% rewritten after Amy left. That explains why it took so long.