I just called an immigration consultant and learned that each time you call CIC, after the call, the application will be put in the end of the queue of that Visa officer's system who is supposed to review it based on the time stamp. Each time we call CIC, our file gets an updated time stamp, that's why it goes to the end of the queue.
However, ordering the GSCM notes won't cause the same, because it is another department abstract the info of our file.
I think maybe I shouldn't call CIC each month, which might have caused me stuck in the end of the queue each time I called.
However, I had another conversation with a friend who had got his pr, he told me he called CIC million times, and hadn't experience any delay.
Therefore, call CIC probably doesn't cause the delay.