for application, you do not need to go the embassy in person. So you can mail your application documents to Canadian embassy in beijing after you have received your assessment. It will take less than three weeks to get the reply.
Another way is you can use your assessment of the previous year. I did that in 2004 and everything went well. I also put my T4 forms in the envelop and note that T4 form will prove my salary of last year.