Provisional figure in online submitted self-assessment tax return

I submitted online my self-assessment tax return 2022 -2023 in January 2024 and I used a provisional figure for the foreign tax paid over my foreign rental income. The reason is why a part of it refers to the period of January 2023 - 5 April 2023 which is not yet due to the overseas country. I will know the actual amount of the foreign tax from August 2024 onwards. Am I obliged to act immediately and amend my submitted self-assessment tax return 2022-2023 as soon as I find out about the actual figure of the foreign tax paid or only when HMRC requests from me to do so? I understand that I have a 12 month period to amend the self-assessment tax return from the deadline 31 January 2024, which is 31 January 2025, is this correct?

Hi,

You should amend it as soon as you know the correct figure and this should be prior to 31 January 2025.

Thank you.