SolvedIEIM740090 | Reporting form and manner
From HM Revenue & Customs · International Exchange of Information Manual
HMRC have provided an online portal through which reports will be made. This is done through a file upload service. A person making a report will need to register with the service first on Gov.uk.
Intermediaries and reportable taxpayers should ensure that reports are complete and correct to the best of their knowledge.
Reports should be made in English.