USCIS published an updated edition of Form N-300, Application to File Declaration of Intention. The new edition is dated 03/30/16. Starting 7/15/16, USCIS will only accept the 03/30/16 edition. Until then, you can use the 03/21/13 edition.
I just passed my interview .
3/11/2016: N-400 Mailed. (Friday)
3/14/2016: N-400 received as per FedEx. (Monday at 10:30am)
4/1/2016: Finger Printing Notice Received. (18 days after they received).
4/12/2016: Finger Printing Done (29 days after they received package).
4/18/2016: Got letter with the interview date (6 days after finger printing, 35 days after they receiving package)
5/23/2016: Interview date
5/23/2016: Interview done. And I was approved
I have read somewhere from another person's experience that if you want a faster Judicial Oath Ceremony, you should take matters into your own hands. What this person did was to call up most of the Judges (District Court?), who can perform such matter, & to ask/request if s/he could perform the service for her. That was how she got hers done quicker than waiting for the normal time frame it takes this type of ceremony to be scheduled. Depending on your DO, it could be a very long time (5-13 months).