The airport operator’s solicitors, CMS Cameron McKenna, confirmed the change in a letter to those preparing for a public inquiry into the plans.
BAA’s revised forecasts reveal it expects passengers to reach 33.9 million a year by 2015, rather than the 38 million set out in the second runway’s planning application.
It now wants to open the expanded airport in 2017, rather than 2015. The government’s 2003 Air Transport White Paper, which favoured expansion at Stansted above all other London airports, aimed for completion by 2011/12.
However, BAA’s long-term forecast remains unaffected. It still expects passenger numbers to increase to 68 million per year by 2030.
Passenger numbers at Stansted have been falling for 13 months. Latest traffic figures show that 11.2% fewer passengers used the airport in January than in December.
Stop Stansted Expansion economics adviser, Brian Ross, commented: "It is wholly unacceptable for BAA to try to keep its options open by continuing to postpone the threat of a second runway."