Thanks for your answer.You're not changing DLI just the program within the same DLI so you don't need to inform IRCC as per the IRCC guidelines. But it is best to change it inside Canada from what I know.
Anyway, I applied for Post graduate certificate which is 1-year program and after I got SP (fingger-crossed) and landed in Can, I would like to change to another Post graduate certificate which is 2-years program (same college), so do I need to inform IRCC to change my SP from 1-year to 2-years?