My brother did everything outside canada just waiting for oath, now he is in Canada since February 2022, no email for oath or anything yet.
Not sure about if you have to email them when you arrive in Canada to start processing the rest of your application.
You can do your oath even with expired pr, also when you renew your pr you can keep your original pr with you, they just need a photo copy of it, also you can't apply for renewing pr until yours expires. This is how I understood it.