Our LEED ND project registered under v2009 in 2015. Although we are currently registered under Stage 3, we still satisfy requirements under Stage 2. It is our understanding that we can change to Stage 2 before October 31, 2016 (when v2009 sunsets), but after that date, we can no longer make any changes to our Stage registration. Any help or insight on answer the following would be greatly appreciated:

1. Is it true that October 31, 2016 is the cut-off date to make any Stage registration changes for a v2009 ND project?
2. What are the pros and cons of registering Stage 2 (planning) vs. Stage 3 (built)?
3. Is Stage 3 a harder certification process since it's based on a final, built project?
4. Would a project truly need as many buffer points under Stage 2 (since it's only a Design certification) than it may need under a Stage 3 project for its targeted certification?
5. If we stick with Stage 3, the ND project still has to have the actual certification from the USGBC by 6/30/21 or it never gets certified, right?
6. Do all, separate building projects (for GIBp1 and/or GIBc1) HAVE to be registered under v2009 (since our ND is under 2009) - and, therefore, by 10/31/16 - or can we add projects for more points (say, under GIBc1) later under LEED v4 for our LEED ND v2009 project?