I have no plans to do so. The provision of taxation services to audit clients is already regulated in two ways:
by the Ethical Standards of the Auditing Practices Board, which auditors are required to follow. These standards require auditors to adopt safeguards to mitigate any threats to their objectivity which might result from their providing tax services, or to refrain from providing the services. by the requirement on companies to disclose in their annual accounts any sums paid to their auditors for taxation services.