On 19 April 2023, a close company (which makes up accounts to 31 March annually) lends £100,000 to Siobhan, who is a director of the company and who owns 30% of its ordinary share capital. The company does not provide loans in the ordinary course of its business. Siobhan pays a commercial rate of interest on this loan until 1 October 2024, when she repays £60,000.

She then continues to pay a commercial rate of interest on the remainder of the loan until it is written off by the company on 31 March 2025. Explain the tax implications of these transactions.