Friday is the day everyone underestimates. The LCBO is open until 9, every grocery is normal, and most of the long-weekend events open at noon. This is your "do it now" day.
By 5 PM, the patio at Auberge du Pommier is full and Yonge & Eglinton brunch slots for Saturday and Sunday are gone. By 9, you've either bought wine for the weekend or you haven't.
The real work of Friday: book Monday brunch. Most office workers are off, and Monday brunch is the busiest of the three days. Reservations open at MIA at 2140 Yonge, Mars Uptown, Oretta Midtown, and Hazel's Diner usually disappear by Friday afternoon.