after your file is transferred Montreal, did you submit application for undertaking and csq (https://www.canadavisa.com/canada-immigration-discussion-board/threads/parents-and-grandparents-sponsorship-2021.744749/page-572#post-10297713). if you submitted, wait for a month and they will send you your approval and csq by post. then after wait again for medical,PPC and ppr to be send to you. this is what happen to me. hope this help
I have not received any request for any additional documents. The last thing we received was approval for Sponsorship. I'm not sure the Undertaking and CSQ is required in this case because my parent is looking to settle in Manitoba and not Quebec.
What is worrisome is that they has been no progress since Feb.