Some more confirmed stores:
Not sure the source on the dates but it is listed in the Barrhaven Blog as such. A lot of the buildings on site at least look like their structures are ready. Perhaps some will open sooner.
Value Village: May 15th
LCBO - June 2nd
Panago Pizza - July 30th
Tim Horton's - Aug 28th
Lone Star - November 11th
A&W - November 28th
Dollarama - Feb 2, 2018
Marshall's - Feb 2, 2018
Sleep Country - March 1, 2018
Ren's Pet Depot - March , 2018
Plus: Tutti Fruiti, Natural Fruit Pantry, Nail Salon, Dentist, Vacuum Shop, SuperCuts, Shawarma.
The above are listed on Trinity's website for the development.
SOURCE - Barrhaven Blog