Kind of late, but I aced my test on the 20th. 20/20. Here's my experience in a short blurb for those still waiting for their test invite. (Note: I am in London)
I arrived a little early and waited in the lobby area. There were about 10 other people who entered and waited. There initially was no IRCC staff to greet anyone, as they were getting everything ready for the tests. The documents I had brought were: my CoPR, my PR card, my expired US passport book, my valid US passport card, my Ontario Photo Card, my (short form) marriage certificate, and Ontario Secondary School Transcript. I also had my Notice to Appear. I will note that I did NOT bring in my cell phone or my purse, as I didn't want to give the citizenship officer any excuse to think I was cheating, but there were people who did have their phones and bags with them.
About 5 or 10 mins before the scheduled test, a citizenship officer came out and asked the test takers to line up and present our PR cards. So we show them and wait again. After we were done, they asked for those who are their for the interview. Once complete, we were escorted to take the test. We sat in the test taking area and were immediately told that everything in the room was confidential information and can't be leaked- so no test spoilers, sorry! What I will say is I was the 3rd or 4th one done with the test- and that was after re-reading the test questions and ensuring I had answered the questions correctly.
Once exiting the testing room, we waited in the lobby again. To my amusement, there was a couple who was talking about the test- go figure. I sat close to one of the interview rooms. There were two rooms and the IRCC officers were calling people in by name; married couples were called in together. When I was called in, I had waited for over an hour. Upon entering the room, I was courteous and polite with the officer, but couldn't help cracking a couple of jokes. She asked to see my documents, but also asked to see my OHIP card, which I didn't bring. I offered to just tell her the number and the version code (I memorized the number because I'm a frequent flyer of the London Regional Cancer Program, where I had to manually input it each visit), but she said it would probably be okay. She asked about my employment status and I told her the whole story as to what was going on with me; basically, I am employed, but on a leave of absence and will be returning to work next week. She gave me a quizzical look, and followed up with asking how I was receiving income, if my husband was employed, etc. I told her my answers and she nodded and seemed satisfied with them. When I showed her my US passport card, she asked if I had a US passport book and I said no, to which she asked why. I simply told her that I only got it because I was going to the States for a mini-vacation in June and that was it- I literally only left the country twice since becoming a PR and had no intention of making a habit of going to the States. She then told me my test results (20/20) and asked me if I had committed any criminal offenses that would prohibit me from becoming a citizen. My answer was: "No, because my dad used to be a cop and he'd kill me!" She laughed super hard and asked me to sign something, and then said that I would receive the Oath Invitation soon.
I have some pieces of advice: one, be on time and don't leave the building because once the test commences, they WILL lock the doors; two, bring a snack because I was there for 2 hours and was getting hungry; three, have your ride or companions wait in the car or have them come get you later- there were people who brought their families for the test and there were people who couldn't sit down due to lack of chairs; four, bring your health card with you; and five, study up before the test and remember that if you do fail, you will just re-take the test and if you fail that, you just talk to a citizenship judge.