statutory board Land Transport Authority (LTA) launched the Bus Service Enhancement Programme (BSEP), with 80 new and extended bus routes only within the general trend and 1000 government-funded buses, involving Volvo B9TL, Mercedes-Benz Citaro, Alexander Dennis Enviro500 and MAN A22 buses. introduced over a period of five years. In 2013, the last non-air-conditioned public bus, the Volvo Olympian 2-axle, was phased out of service whereas SMRT Buses introduced its first wheelchair-accessible articulated bus, the MAN A24 and in the following year, its first-ever double-decker bus, the Alexander Dennis Enviro500. In 2014, LTA announced that it would replace the existing operating model with the Bus Contracting Model (BCM) from 2016 onwards. Modelled after the Transperth model with elements of the competitive tendering model from London Buses, LTA would own all bus assets and lease them out in regional packages to different bus operators for five years. The first bus package, the Bulim Bus Package, was awarded to Anglo-Australian company Tower Transit whereas Loyang was awarded to Go-Ahead. Both companies began their operations in 2016. The entire public bus system was fully transitioned into the BCM by September 2016 with SBS Transit and SMRT signing agreements with LTA to operate the remaining packages up to 2021 to 2026 after which they would be gradually opened up to competitive tendering. With the BCM, bus operators introduced new buses with new features; in 2016 the first fully electric bus since the withdrawal of trolleybuses, the BYD K9A, was operated by Go-Ahead Singapore whereas the first buses with USB charging ports commenced service with SMRT that year. In 2017, two three-door buses — a double-deck MAN A95 and a single deck MAN A22 were trialled by Tower Transit and SMRT Buses respectively. New Volvo B5LH hybrid buses were also purchased from Volvo in 2018. On 17 December 2018, LTA started a 6-month trial of on-demand public bus (ODPB) services. It allows commuters to request on-demand bus services within the Marina-Downtown and Joo Koon areas during off-peak hours on weekdays, and those heading from the CBD to Bedok or Tampines late-night hours. During the trial, regular bus services serving the areas specified will still be available, though at lower frequencies. However, the trials were unsuccessful and were eventually discontinued after 15 June 2019. As a result, services 400 and 402 were merged into Feeder service 400, from Shenton Way to Marina Barrage and Marina South Pier