Yes, that is what I am wondering as well. But an applicant in China mentioned she sent the passport to VAC Beijing on March 10 and get the "big yellow envelope" back on March 13. Maybe an extreme case, as I know Beijing VAC started taking passport on March 9 and there may be not any submissions at that time. My wife's passport arrived in VAC Beijing on March 12 (it took 2 days to deliver the pass in the city!) and was dispatched to embassy on March 16 and is still in the embassy for processing.
The exemption is not in place yet. Though theoretically, they are allowed to enter Canada, in reality, they have to wait until the exemption is in place.
Workers, students and approved permanent residents who haven’t landed should not travel yet. We’ve announced exemptions but they’re not in place. Travel restrictions are still in effect for these groups.
Only Canadian citizens, and permanent residents, and some foreign nationals travelling from the United States (US) who have been in the US for at least 14 days and are asymptomatic, are able to enter Canada by air at this time.
https://www.canada.ca/en/immigration-refugees-citizenship/services/coronavirus-special-measures.html