I'm sorry, guys, but it's just insane (not just csang, everybody with similar attitude). Someone who sent his application three days later than me got a test invitation, and I didn't! Should I be concerned, alarmed, panicky, wring my hands and hit my head against the wall? This is not kindergarden. How come you are still alive if you are always ready to freak out for no reason whatsoever??? A friendly piece of advice: citizenship processing time is 12 months. Forget about your application and when/if you don't hear from immigration by October 2018, then maybe you will have a reason to be concerned. But even then there will be no reason to get "alarmed". Life goes on, with or without the Canadian passport.
If you think I'm not in your shoes, my status went IP on Nov 22, and I don't give a shit if I get a test invitation next month, in March, or in August. It will come sooner or later.