Split year treatment for domicile of choice

I am registering for Self Assessment for the first time, in order to pay tax on dividends in the US. I have lived in the UK for 6 years as a student, and my dividends have therefore been non-taxable in the UK under the terms of the UK-US tax treaty. However, I have adopted a UK domicile of choice, and therefore my understanding is that the dividends are taxable in the UK. When registering for Self Assessment, I must report the 'date started receiving taxable foreign income'. My rough deduction is that this should be the date of the first dividend received after adopting UK domicile, as adopting a domicile of choice would create split year treatment (maybe under case 4) for income that was previously untaxable. However, I have been unable to find clear HMRC guidance that this is correct.

Hi,

We can only refer you to the guidance on residence.  It is up to you to decide whether case 4 applies to your circumstances.  If split year treatment applies, then you only need to declare that

split year treatment applies and the dividends arising after the split, where the dividends are taxable.

Thank you.