What should I do if I can't have a physical examination within 30 days after IRCC Canada's renewal?

Write an email to the Canadian Immigration Bureau, specifying the extension and the fastest physical examination time. They agreed and will send you an email asking you to postpone it. This problem is not difficult to solve.

There is another way, that is, you can make an appointment for a medical examination in a different place, and you can have a Canadian medical examination in any city in Chinese mainland. Some cities have a large number of physical examinations, and some cities have a small number of physical examinations. You can still submit a medical examination when you make an appointment for a medical examination in a city with a small number of medical examinations.