It's official: the city won't get the keys to an operational Confederation Line on the date expected — for the fourth time.

In July, Ottawa Mayor Jim Watson said he expected the new LRT system would be delivered to the city by Aug. 16.

But a memo sent to the mayor and council Friday morning from transportation general manager John Manconi said 12 consecutive days of trial run testing are ongoing, and that LRT system builder Rideau Transit Group (RTG) has made "significant progress."

"This is a complex and rigorous process where high performance standards must be met as a prerequisite to achieving [revenue service availability] and opening the Confederation Line to the public," he wrote.

In spite of this latest missed deadline, Manconi said the city continues to expect that the Confederation Line will open to the public in September.

An update from Watson, transit commission chair Allan Hubley and city staff will be given at a briefing sometime next week, Manconi added. A date has not yet been set.