Hi, I understand how frustrating it feels because my SMC application timeline is almost like yours.
My AR is 22nd Sep 2017 too. After that, I waited abt 6 months until a CO emailed my employer to check my job at the end of the last month.
My employer replied the questionnaire a week ago, and I am waiting for the response from INZ now.
I never asked INZ about my NSC status, all I know is my AR email received on 22nd Sep from INZ says they are "waiting for information to be provided by a third party, which could take up to 6 months." So, hopefully, my NSC is done.
I know other ppl got no response from INZ as well, guess it is very common now.