OK so the timeline in signature is really my spouse's. I was on the same timeline till FP. The DO today replied to my query that my case is waiting for 'FBI Name Check to clear ' after which I will be placed in queue to be interviewed. Now there are some horror stories about FBI name check. What are my options here? Senator? Visit the local FBI field office? What else?
What is your DO? Did you check what their official processing time for N-400 is?
https://egov.uscis.gov/cris/processTimesDisplayInit.do
It has been less than 3 months since you submitted an N-400, and you are still well within the normal processing times. There is not much point in bothering with the Senator, U.S. Representatives, CIS Ombudsman, etc that quickly.
The FBI Name Check is very unpredictable: it could be completed tomorrow, or it could take over a year (although the latter is rather uncommon now), you never know.
I'd say that you should wait about 6 months from the N-400 filing date and then start making some noises (Senator, U.S. Representatives, CIS Ombudsman, DO inquiries, e-request, and so on).
Keep in mind, however, that making these inquiries will not speed up your NameCheck processing. However, you should still be making these types of inquiries if you are still not scheduled for an interview by that time. First, that'll give you up-to-date information. Second, if you do end up having to file a lawsuit later, you'll need to have a record of having made significant effort in clarifying the status of your case.
If about a year from the N-400 filing date your Name Check is still not completed, you should then consider filing a lawsuit against USCIS in federal court, requesting a writ of mandamus to force USCIS to adjudicate your application. This is the only thing that, based on past experience when Name Check delays were common (until about 4 years ago), that can actually result in speeding up the NameCheck.
See the thread
http://forums.immigration.com/showt...-or-thinking-about-a-lawsuit-(Merged)/page597 for info about filing a lawsuit.
I myself was stuck in the NameCheck for over 2 years during my N-400 processing and I now regret not having filed a lawsuit after the first year.
Still, in your case it is more likely that your FBI NameCheck will be completed in the next few weeks, and hopefully you'll not need to wait as long as I had to.