In addition to the points made above, it's worth reviewing HMRC's Spotlights website. The use of loans as a tax avoidance measure is discussed there, along with HMRC's plans to systematically review/investigate numerous schemes - the purpose of which is to close them down and retrieve taxes/penalties from individuals.
This could be seen as 'retrospective' from an individual's point of view i.e. the individual joined the scheme in good faith, received tax-free (or low tax) payments for many months/years, but will now be asked to pay tax on them by HMRC.
This could be seen as 'retrospective' from an individual's point of view i.e. the individual joined the scheme in good faith, received tax-free (or low tax) payments for many months/years, but will now be asked to pay tax on them by HMRC.


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