Now that the Queen is dead, there are many things that need to be legally changed - oath text, oath forms, certificates, passports and who knows what else behind the scenes.
Unfortunately expecting more confusion and delays around this now, as if the current delays weren't enough.
Here's some recent confusion that happened at the last oath ceremony -
https://nationalpost.com/news/canada/thats-wild-new-canadians-swear-citizenship-oath-to-king-charles-iii
The oath form that one signs and emails needs to be changed as well. The one that's received with the rest of the oath email stuff.
Even after oath they'll need to switch to new citizenship certificate and passport copies before issuing them.
Staying optimistic but going by their/IRCC's past record, which is poor I'm not expecting these changes to go smoothly. Gladly waiting to be proven wrong.