It takes more than 3 months to prepare NDA Filing. You are dealing with FDA and will not want to hear from it this is missing, that is unclear, etc. etc. etc. Q4 filing is reasonable and has nothing to do with confidence.
PPS is not related to the timing of the filing. The volatility will not end until the end of Q3. See the option expiration dates, today, 08/23, 08/30, 09/06, 09/13, 09/20. #$%$, PPS will move drastically. I will not be surprised that PPS will touch $9 again within a week or two.
I doubt they are "waiting". It takes time to analyze al the data. Sometimes one finding begets more questions which then require further analysis. There are lots of variables to examine and many ways of cutting the data. Conclusions need to be drawn and interpretation of the data agreed upon. Then it all needs to be put in the proper format before submitted. 4th Quarter is only 6 weeks away. Relax.