Just wanted to share my timeline and most importantly my first hand experience at the London ON passport (not Service Canada) office.
Paper Application submitted/received: March 28th 2021/April 1st 2021.
AOR: July 13th 2021
Background check completed: September 3rd
Citizenship test invite: December 13th
Test taken: December 21st
Language/Physical act./Prohibition activity updated: February 25th 2022
Oath ceremony update: March 23rd
Oath taken: April 5th
Citizenship certificate issued/received in mail: April 8th/April 12th
London ON Passport office experience
Went on Apr 21, 22 and 25 @ 8:30am when the office opens up to do reconnaissance. Incredibly long queues as we are all aware (bear in mind, these are only people who want passport issued/renewed in 26 business days or less with travel proof). One of the official came out @ 8:30am and announced that they are only accepting applications for travels on or before 26 business days from that respective date. Also, people who have to travel in the next 2 business days can jump the line and go to front (there was a separate queue inside for these 'urgent' applicants and another regular queue for people who had been waiting since 5-6am onwards). In terms of travel proof she mentioned, I found it to be too loose and relaxed: air/bus tickets or Air BnB/hotel or just a written statement behind your application as to where you are going and why so they can make a copy of it.
I booked a ticket to Washington DC (free cancellation in 24 hours) for the long weekend in May (May 20-23) just to get the passport as a new citizen. Reached the London office April 26th @ 6am and was #7 in the queue. As soon as the office opened at 8:30, the lady came out and made the same announcement and some people behind me went straight to the front. Security guard checks your travel proof before ushering you in the regular queue. I first went to the information window (took an hour to reach there at 9:30am) where the employee behind the counter checks your application/photographs/travel proof and confirms your travel dates, and gives you a ticket. Please note that of the 17-18 counters, only 4-5 were operational (and at any single point in time, one of the counters would be missing an employee for 10-15 mins) I then waited in the lounge area till 10:30am when my ticket was called. Took 5 minutes in my case but most of the cases were taking 10-20 minutes each. I can pick up my passport on May 10th (2 weeks processing time for a $20 fee. You cannot choose a faster processing by paying a higher fees as it's being done by date of travel).
My advice to the forum members:
If you don't mind getting up early and waiting in the queue for a total of 4-5 hours, do what I did. I could have gotten the ticket for 3 days out but I still want to respect actual urgent travel needs people may have. Otherwise, book a fully refundable air bnb anywhere in the US east coast that is driveable and show that as your travel proof.
Hope this helps! Good luck!