They later send med who go to Quebec, coz these guys do not work very fast ... they are forced to send a request later, or people need do med again (there are many such cases) or have a short period for landing (i.e. until the end of the medical exam). But Quebec is part of the statement, there are probably other reasons.
That sounds like it would explain a lot, I did not look closely to see if intended destination province matched the cases where med request sent later.