I am sure people can answer this better than I can, but:
1. IMO, a week ahead is more than enough time, especially if you have previously prepared for TIs/VIs/HR interviews.
2. By this stage, you should have your competency and motivational Qs pretty much nailed on. If not, do not panic, just keep revising them over and over, speaking out loud and practicing with friends + family.
3. From my experience, I spent the 3-days before my final interviews memorising a few deals, key relevant commercial themes, growth areas of the firm and its recent news [office openings, lateral hires, new practice areas (ESG)]. During the interviews, this was hardly covered, although this will of course vary.
At the end of the day, if you do all of this, it will be stored in your 'subconscious filing cabinet' and you can then pull out what you need, as and when.
Just be yourself, be confident, smile and you will be fine! From my experience, try not to guess 'what they want' or 'what a usual applicant would do', because interviewers can read you like a book.
Hope that helps.