If this has the title "Reminder" then its just the reminder indicating if you haven't submitted already, do so now. If it has a date specified and has wordings like "we need your medical results" then its instruction letter.
I received similar kind of thing yesterday and turned out it was just a reminder, I got my status updated as and "Medicals passed" today. I think they are considering older medical results basis following exemption:
When to get your medical exam
In-Canada permanent residence applicants
You’re exempt from completing an additional immigration medical exam (IME) if
- you have applied, or you are applying for permanent residence and
- you are already residing in Canada and
- you have completed your immigration medical exam in the last 5 years and
- an IRCC medical officer found your medical exam as low risk or no risk to public health or public safety
If you’ve already completed an IME and are applying for permanent residence, make sure you provide an IME number (or unique medical identifier number) from your previous medical exam in your application.
Learn more about the temporary public policy, which is in effect until December 28, 2021.
Read the
instruction guide for your program to find out if you need a medical exam and when to get it.
(Source Link-
https://www.canada.ca/en/immigratio...ms/requirements-permanent-residents.html#long)