HMRC provide an “Agent Dedicated Line” for those formally authorised to act as an agent or tax adviser. The line deals with queries about self-assessment and PAYE.
During January 2023, the line will only be able to answer complex self-assessment queries. It will not accept calls made “to check progress or ask about tax and employment history”.
The line is open from Monday to Friday, between 8am and 6pm, but is closed on bank holidays.