Toronto’s city council is expected to postpone until March an executive committee meeting to review Porter Airlines’ request to operate Bombardier CSeries airliners from the city’s downtown island airport. This could lead to a full city council vote on April 1.

But city staff are pushing to delay to March 2015 a decision on the proposal to extend the runway and lift the ban on operating jets at Billy Bishop Toronto City Airport (BBTCA). Porter placed a conditional order for 15 Bombardier CS100s in September, and plans to begin operations early in 2016.

Any changes at BBTCA must be approved by the city council, Toronto Port Authority (TPA) and the Canadian federal government under the Tripartite Agreement signed in 1983. This restricts operations to turboprops, and Porter currently operates Bombardier Q400s.

The airline had hoped for a vote in December, but is playing down the delay. “This updated timeline is a good sign that the three parties are making progress on a plan for the future of Billy Bishop Toronto City Airport. Porter supports the work being done and this timeline,” an airline statement says.

Porter has proposed lifting the ban on jets and extending the runway by 200 meters (660 ft.) at each end to accommodate the 107-seat CS100 and allow reduced-thrust departures for lower noise. The airline argues that the twinjet will have noise levels comparable to the Q400.

But at a public meeting on Jan. 28, city staff argued that approval of Porter’s request is premature. Outstanding issues included confirmation of the feasibility and impact of the runway extension, and insufficient flight-test data on the CSeries.

Another issue cited by city staff is a Jan. 24 request by the port authority to extend the tripartite agreement beyond its 2033 expiry date. The TPA says the extension is necessitated by Porter’s plans to operate jets from BBTCA.

The port authority also surprised the city council by announcing its was seeking C$100 million ($90 million) from the federal government for ground infrastructure improvements at the downtown airport, to handle the anticipated increase in traffic.

Independent reviews of the proposal are based on the assumption that passenger traffic at BBTCA would increase to 4.3 million passengers a year from 2.3 million in 2012, within the current cap of 202 movements a day, when Porter upgrades to the larger CSeries.

With some studies suggesting that traffic could increase to 4.8 million a year if the self-imposed cap on movements is raised, Toronto city staff have recommended further studies and consultations, as well as development of a master plan and capital works program for BBTCA.

City staff have recommended that they be directed to report back in March 2015. Although Bombardier has pushed back the start of CSeries deliveries to the second half of 2015, this would likely be too late for Porter to confirm its order and receive the aircraft by early 2016.