If the employer's establishment is normally open on Sunday, the public holiday pay rules apply to that Sunday. Where businesses are normally closed on Sunday, and New Year's Day, Christmas Day, or Remembrance Day fall on a Sunday, the following Monday is observed as a public holiday.
Canada Day is covered by federal legislation. Currently, federal law says when July 1 falls on a Sunday, the holiday is observed on Monday, July 2.
Note: When a public holiday falls on a Saturday, it is not observed on a different day.