EM3915 | Concluding the Enquiry: Calculation of Duty Lost: Years to be Included
From HM Revenue & Customs · Enquiry Manual
Your computation of tax and NIC lost should include
all relevant duties recoverable by assessment
all years of assessment and chargeable periods.
These will go from the date of the earliest underassessment up to the end of the enquiry period in so far as the duties are recoverable by assessment.
Where tax and NIC is no longer recoverable by assessment, refer to EM3980.
No assessment may be made later than the time-limits at EM3214.