Split treatment & double taxation rules

Hi, I have been living and working in the uk for the last 8+ years. I spent 137 days in the UK this tax year. I have been in Spain since mid September and will be starting a new job in Spain from early October, I am also in the process of getting my residency. I want to make sure I understand if I remain to be liable for tax on my Spanish income for the rest of the year/until I become a tax resident here. Am I applicable for the split year treatment? Should I be informing HMRC now or only once I start the new job? I don't have plans to return to the uk in the next 3+ years. Thanks

Hi shahaha,
If you qualify for split year then you only report any foreign income for the UK part of the year.
RDRM12000 - Residence: The SRT: Split year treatment: Contents
If you do not qualify then you will need to report all your foreign income to the UK:
Tax on foreign income
The guidance at:
RDRM12150 - Residence: The SRT: Split year treatment: Case 4: Starting to have a home in the UK only
Will help you work out if split year treatment applies.
Please also refer to:
Tax if you leave the UK to live abroad
Thank you.