UK/Portugal split year - online self-assessment

Hello, I was a UK resident employed in the UK until July 31, 2022 with a single source of income from this employment. I became a resident of Portugal, employed in Portugal on August 2, 2022, pay taxes in Portugal. I have not had any UK-originating income since I moved to Portugal. I received guidance here that I need to report my Portuguese income and pay taxes on it in Portugal only: https://community.hmrc.gov.uk/customerforums/pt/ebb2cf40-382d-ee11-a81c-000d3a8751e3 Meaning, I don't need to report my earnings in Portugal to HMRC. Can I use HMRC's online self-assessment for the part of the year when I was a resident in the UK and was employed in the UK?

Hi PF,
You will need to review the statutory residence tests to determine whether you will be considered tax resident for the whole tax year or not tax resident for the whole tax year.
If you are deemed tax resident, you will need to check whether split year treatment applies.
If it does, you will need to claim this on SA109 as part of your 2022 to 2023 tax return.
RDR3 Statutory Residence Test
Thank you.