I 'm in similar situation , parents are in Canada since October 2021, and already informed them change of address when my parents arrived.
On February 02, 2022 , I got pre-arrival service letter(Passport request) , and I sent them immediately change of address and don't need to send them Passport coz it consider as Virtual landing. Since then no updates, I call them and they said , need to wait. Very surprise to see how long they took time to process to issue Co-PR if parents are already in Canada , I'm very very frustrated to see this IRCC system very much chaotic. Feeling helpless the way they handling immigration