When will all buses and coaches meet PSVAR?
All full size single deck buses over 7.5 tonnes will be fully accessible from 1 January 2016, and all double deck buses from 1 January 2017. New buses weighing up to 7.5 tonnes and coaches will be required to have wheelchair access from 1 January 2005. All buses weighing up to 7.5 tonnes will be fully accessible from 1 January 2015 and coaches by 1 January 2020.
Source - gov.uk/government/publications/bus-coach-accessibility-faq