Because there is no set order for a CO to follow when processing a case, there is no way to tell which are 'final documents'. It could be that the CO will still have other requirements for more evidence.
And there is no way to tell how things are going for the CO, waiting for verification (replies from other people) about the evidence already submitted. Sometimes, people don't see anything urgent about answering a CO's questions, or the right person has just gone on a month's holiday or maternity leave or something, and the CO can do nothing more but wait till they have received the LAST reply. Always, with INZ, it is a matter of 'it takes as long as it takes'.