SolvedCH64280 | Penalties for failure to file on time: how to process a penalty: cancellation of penalties
From HM Revenue & Customs · Compliance Handbook
Where we decide that a person does not have to file a self assessment (SA) tax return we can withdraw the obligation to file that SA tax return, see CH61700.
If we agree to withdraw the obligation to file an SA tax return then any penalties for failing to file that SA tax return on time will be cancelled.