The GCMS refers to the program called Global Case Management System (GCMS) used by IRCC that holds the entire processing record of your application, including the the notes pertaining to eligibility by an officer evaluating your file.
All applications go through the following stages:
R10
Medicals
Criminality
Eligibility
Security
R10 or the completeness check is the first stage of the processing, wherein it is verified that your application is complete and all documents are submitted. Filing a complete application is the responsibility of the application, and if a document is missing, a reason and an exemption request should be filed.
If an application is incomplete, it will be rejected. R10 usually happens within 30-45 days of filing your application, around the time when medicals are passed. The exact date will be available in your GCMS notes.
There is no point requesting GCMS notes at this stage, since if your application is incomplete, it will be rejected anyway, and for the medicals, the MyCIC account does inform you of when your meds are passed.
GCMS notes become important only for the eligibility stage, which does not start until 3-4 months. Eligibility takes place in 2 stages. First a case assistant or an analyst will review and make a recommendation. This is then reviewed by an officer who makes the final decision on the eligibility. Since each document you submitted has to be reviewed twice, this is the most time consuming stage.
Only for this stage are the GCMS notes relevant.
While GCMS is a great tool, use it sparingly and only after 3-4 months have expired.
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