According to published reports from Bombardier, the company plans to have the maiden flight of the prototype CSeries aircraft completed by September 17th, 2013.
Bombardier will host an event at its facilities at Mirabel on September 17 for employees and other stakeholders and plans to have the CSeries prototype present on display at minimum with the goal of having the aircraft perform at least one flyover of the proceedings. The manufacturer is uncertain at this point whether that will be the first flight date, which is dependent on weather and other factors.