From the Government of Ontario Covid-19 site:

https://www.ontario.ca/page/reopening-ontario-stages#gathering-changes

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Changes to gathering limits

Due to the recent increase in cases and to ensure continued health and safety, there is a new limit on the number of people allowed to attend unmonitored social gatherings and organized public events across Ontario.

As of September 19, 2020, the new gathering limits are:

  • indoor events or gatherings: 10 people (previous limit of 50)
  • outdoor events or gatherings: 25 people (previous limit of 100)

Indoor and outdoor events and gatherings cannot be merged together.

This applies to social gatherings in private residences, backyards, parks and other recreational areas. This includes:

  • functions
  • parties
  • dinners
  • gatherings
  • barbecues
  • wedding receptions

The new limits do not apply to events or gatherings in staffed businesses and facilities because they must already follow specific public health and safety guidelines to minimize risk and limit the spread of COVID-19. They include:

  • bars
  • restaurants
  • cinemas
  • convention centres or banquet halls
  • gyms
  • recreational sporting or performing art events
  • religious services, rites or ceremonies

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They don’t mention… FINES!  $10,000 for the host; $750 per “friend”.  I hate to think what will happen if you all happen to be SINGING when the cops show up.  Singing is a “high risk activity”.