Thank you for replying.MyCIC shows the exact date of medical pass and I think that is relevant to expiry of PR visa. Ecas only states Medical Received without date.
I heard before that the medical exam result is only valid for 12 months, but I am not sure if it counts from the day medical exam was done or the day the medical exam passed.
MyCIC did show the medical passed in March 2020. I wonder if it is valid until March 2021. Meanwhile, my mom didn't have an additional test, but as a spouse, her medical passed date is the same as the PA. It doesn't make sense that her medical exam result can be valid for 16 months just because the PA conduct addition tests.
Of course, if there is no expiry on medical exam result, that will be perfect.