Hi. I would rather trust the official CIC information what they say. I was exactly like you, I came here as a visitor to visit my boyfriend and to travel within Canada, i been here for 6 months and wanted to extend my stay. Even tho CIC says "apply at least 30 days before" i read this forum and i saw all the people saying "1 day before status expires is enough" so I trusted them and applied a week before my status expired. My application was refused and the reason was "your application was not submitted on time". So, apply at least 30 days before your status expires otherwise you could have same problem as I did