Just got another GCMS note which is almost identical with the previous one the former was 96 whereas the latter is 97 - still identical.This is much better. I have highlighted all the good points above. The security will read 'Not Started' until the application is finalized and you get PPR AFAIK. From the information that you have provided, looks like your security checks has begun and is underway.
In some cases, your case could be referred to CSIS for further scrutiny (As a part of random quality check or if there is a name / DOB match in the database etc). In that case, CSIS has to do further checks and then provide a report to IRCC after which IRCC will continue further processing of your application. See if you find anything in the notes that indicate your file was forwarded to CSIS (And I really hope this isn't the case).
Just curious, do you have a long international travel history?