The move is also part of the tax authority’s drive to force people to use online services rather than calling helplines.  

In a letter to the Treasury Committee, HMRC deputy chief executive Angela MacDonald said: ‘The decision to pilot a seasonal telephony model for SA was taken based on the need to improve overall customer service levels.

‘This is also set against the context of the challenging level of efficiencies required by our Spending Review 2021 settlement. This challenge has been subject to further pressure from inflation and policy decisions, directly impacting the number of taxpayers, and the number with more complex affairs, that we have to serve.

‘We recognise that this pilot will test a significant change in our services and will need careful monitoring, but our analysis shows that we should be able to handle the vast majority of SA queries over the summer through our digital service, backed up with a webchat adviser service.