It seems we are in similar situation. I has asked to give my first medical for PR on September 1, 2020 and gave the medical on September 4, 2020. It has been almost 2.5 weeks and nothing yet. I am hoping to hear from them this week. At least hoping to get Medical result received message this week.
As
@imissmylove suggests; every officer is different. Some of them request medical early some of them later. Some of them extend your medical in order to finalise your your PR. That happened to me. My medical extended because my security and background has been completed. But then COVID 19 hit.
If your background and security check has been completed; you will get medical result received and AIP and COPR one after another.