I have been asked to reply.
There are, as yet, no firm plans to amend the Clean Air Act 1993 in response to changes in fuel use patterns in Scotland.
The Clean Air Act 1993 is an important part of the regulatory system which is helping to improve air quality and protect public health. Its provisions cover the whole of the UK and any changes to it need to be considered on that basis. Such consideration will need to take into account the different ways in which the UK's Devolved Administrations will seek to deliver the increases in renewable heat and energy needed to achieve the UK's obligations.