Someone just posted this in the Canadian Citizenship Test group (on FB):
"Application delivered via paper mail: December 2, 2020
Received AOR: Feb 13, 2021
Started processing: Feb 28, 2021
Test Invite: April 15, 2021
Took test: April 19, 2021
Location: Toronto
Decision Made: TODAY!!!!!
Single, not-urgent application."
After my 30th March interview, my status was still "in progress" on 16th April (confirmed through calling IRCC; still can't check my status online haha). Tbh I can't help but compare a little; still I'm not complaining coz I've been pretty lucky too being an early online application. Bottom line: this shows paper based applications can also get quite lucky.