Claim relief on the basis of the DTA via self assessment

Hello, I moved to Spain in June 2023 and spent more than 183 days there, making me a tax resident in Spain for the entire year 2023, as Spain does not have a split tax year. I worked for a UK employer until May 2023, and before permanently relocating to Spain, I worked remotely for my UK employer in February and March 2023 from Spain. For the tax year 2022/2023, based on the Double Taxation Agreement (DTA) 14.1, I would like to claim relief for the working days in Spain in February and March 2023. During that time, I had a permanent home in Spain, and my family already lived there, establishing my center of vital interest in Spain. Although I am still a UK resident for 2022/2023 due to working full time in the UK, I am also a resident in Spain. My understanding is that, as part of the self-assessment, I need to fill in SA109 and HS302 to provide information about my residency and claim relief for the working days in Spain, as I am required to pay tax there for the entire year 2023. Could you please confirm that my understanding is correct? Thank you in advance. P.S. I am aware that to complete SA109, I need to use commercial software.

Hi Artimida1111,
Your understanding is correct.
Thank you.