My wife's I-485 case got approved today in NSC. Got the magical text at 3:00 PM ET today. We both had applied for I-485 in TSC on Nov 3rd, 2016. Spouse case got transferred to NSC on Jan 27th, 2017. My (primary) I-485 case got approved on March 9th, 2017 in TSC. Wife's I-485 got approved in about 11 months (NSC processing time for employment based I-485 is Dec 2, 2016 as per July 31st, 2017). Thank You all for all the posts and your experiences. Good Luck everyone. Below is the brief timeline for wife's I-485.

EB2 Dependent
Nov 03, 2016- I-485 application filed for both primary and dependent
Nov 04, 2016- USCIS Received date
Nov 08, 2016- USCIS Notice date
Dec 01, 2016- Fingerprint date
Jan 27, 2017- Case transferred from TSC to NSC
Feb 01, 2017- EAD & AP approval date
Feb 08, 2017- EAD & AP received date
Mar 09, 2017- Primary I-485 approval date
Jun 28,2017- First online SRC raised by applicant
Jul 13, 2017- USCIS email reply on how SR will be handled, advised a notice within 60 days
Sep 26, 2017- Discussed with lawyer since it was more than 60 days. Lawyer advised that aggressive inquiry were generating some RFEs but we decided with my lawyer that they will call USCIS. Lawyer called USCIS and they advised to open another SR. Lawyer opened another online SR.
Oct 4, 2017- USCIS email reply on how SR will be handled, advised a notice within 60 days. This was the same email that we received on July 13th, 2017.
Oct 10, 2017- Dependent I-485 got approved, got the magical text around 3:00PM. I have read in many immigration forums that the interviews for I-485 will be scheduled for applicants who have filed I-485 after March 6th, 2017. Dependent didn't need to go for interview, so it looks like this got applied in my dependent's case.

Good Luck everyone. All we can do is be positive and hope for the best outcome.