There is a CBC news story about the change at http://www.cbc.ca/news/canada/ottawa/city-extends-parking-hours-on-residential-streets-1.4689277 and the city has a press release at https://ottawa.ca/en/news/heres-sign-times-traffic-and-parking-law
The more complete list of parking rules (and fines) is at https://ottawa.ca/en/residents/transportation-and-parking/parking/regulations-and-restrictions Lots of special cases like “Park within 9 m of intersection” in that list.