Im almost Canadian citizen( few days from the Oath), and can share my story.
1- I’m applicant July 2020
2- Finally interview on September
3- Oath in October
But the most important is to tell what I saw .
The same day of interview, applicants from 2018-2019 had been taken the ceremony of citizenship.
4- I had been noticed to take the Oath, 2 days after Decision Made and 3 days after interview with IRCC, Scarborough office.
5- There are NO rules, I begin to believe in luck