Actually to be precise and due to 2020 being a leap year, the specific dates can be found with the following link:
https://www.osc.gov.on.ca/en/Companies_filing-calendar_index.htm
So, the 2019 y/e report is due to be filed on or before April 29th and Q1is due to be filed on or before June 1st.
Hope this helps
Hogan