Without warning, after April 11 (information posted April 12) IRCC has discontinued the policy of allowing applications to be filed with documents missing due to COVID-19. See the updated instructions here: https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/service-delivery/coronavirus/general-measures.html
Applications previously submitted with documents missing will be given 30 days notice to bring the application to completeness or provide a specific explanation for why more time is needed.