Well, that "someone" fed you with misinformation. What that "someone" said is not correct.
There are no tags on the GCMS notes that would classify an application as routine or non-routine. Routine/Non-routine is not exactly an application status - It is just an understanding that is based on the facts of the case. For example, if IRCC wants to scrutinize your physical presence and sends you a Residency Questionnaire (called RQ), then the general understanding is that this particular application is considered "non-routine" (You won't actually see the words "non-routine" anywhere AFAIK). So, if you see an impending RQ request on your GCMS notes, for example, you can assume that the application is non-routine. Other than that, there are no tags anywhere on the GCMS notes (at least none that I know of) that will explicitly say "routine" or "non-routine".
Here's IRCC's take on what could constitute non-routine:
https://www.cic.gc.ca/english/helpcentre/answer.asp?qnum=1169&top=5