HMRC have announced that:
“Between 17 April 2023 and 2 June 2023 the Agent Dedicated Line (ADL) will only answer calls relating to Self Assessment late filling penalties and appeals and PAYE coding enquiries.
For all other enquiries you will need to use our online services or the main helplines where you will get answered, although it may take longer than usual. The ADL will not answer any progress chasing calls. This is to make sure that we can give the best possible service to all customers at one of our busiest times.”