Ok you made yourself a potential big big problem. That answer may have been entered into the system as a comment to your return to Canada. So yes for next 5 years from October 2019 I would not try to renew your PR card if I were you. One of the thing you must mention and prove correctly for your card renewal is days stayed in Canada (so that would be showing leaving or returning stamps in your passport and flight tickets). And yes they can come across that statement from October and find inconsistency.Actually there was something:
When I landed in Montreal on Oct 31 I got my PR card scanned at one of the kiosks, answered all the questions, took the white printout and showed it together with the PR card to a border officer. He asked me "When did you leave Canada". Not being prepared for such a question I got uncertain for a short moment but tried to remain calm. I answered "End of September" which was not correct since I actually left by the end of August but I felt it would be better to mention a date which was not too long ago and after the PR card was issued to me. He did not ask any further question, made some kind of marking on the printout and let me pass. Of course I did not feel good, since I was actually lying to a Canadian official. However, as far as I observed it, he did not write down anything, or made any kind of recording.
Once that is passed chances of that to be discovered are much smaller (as you are not asked about details that are older than 5 years ago).