All passenger rail vehicles must be accessible by 1 January 2020. The Department for Transport has identified heavy rail fleets which need to be made more accessible to allow the use of the units beyond the legal deadline.

Details of the level of accessibility expected on this fleet by 2020. This follows assessment of a unit, and consultation with the Disabled Persons Transport Advisory Committee (DPTAC). It may also include any dispensations that have been granted in relation to this fleet.

https://www.gov.uk/government/publications/heavy-rail-fleet-angel-trains-class-156