Can trust income be backdated?

I'm a beneficiary of an Interest In Possession trust that hardly ever pays anything out. Months after I completed my 2023-2024 tax return, the trustees and accountant sent me an R185 saying I had received income from the trust in that tax year. Actually, I didn't receive anything from the trust that year (or know about this at all), but the trustees/accountant say they will send me the money soon (it's now 8 months after the tax year ended). Is it legal that they are paying me the income in the 2024-2025 tax year, but saying it's from the 2023-2024 tax year? For my own tax return, should I personally treat this as 2023-2024 or 2024-2025 income?

Hi,
As the income arose in the actual trust in 2023 to 2024, it needs to be declared as 2023 to 2024 income.
Thank you.