Tax liability for first 15 tax years as UK resident

Hello HMRC admin, Hope you are well. I am writing on behalf of a friend who needs some help. She is a British citizen (born in India but naturalised here, her father was also born in India) and has been living in the UK for past 17 years. The money that she earns here (PAYE) in the UK is sent to India to be invested in NRE Fixed deposits (never claimed remittance basis on that). The questions are as follows: 1. Is it true that she is not liable to pay tax in UK on foreign interest gained as she is a non-domicile for the first 15 years of her stay in the UK? Also, does this rule apply to any specific source of foreign income or any overseas income eg. interest from fixed deposits vs rental income from property overseas? As mentioned on gov.uk website about deemed domicile rule, it states that after you have lived in the UK for at least 15 of the 20 tax years, you become deemed domicile (condition B) and thus need to pay taxes on the interest generated on savings abroad. Does that mean from 16th tax year she needs to declare her foreign interest gained and pay tax in UK as she becomes a deemed domicile? 2. If she decides to bring back her investments from India to UK which are in the form of principal amount that she had transferd to india over 15 years (being a non-domicile) plus the interest gained, will she be liable to pay tax again in the UK for bringing it back? It is obvious that she had paid the UK tax on the principal amount before transferring to India. Your help would be much appreciated. Regards

Hi
She would need to apply for non domicile status on the tax return to confirm that she is claiming the remittance basis in order not to declare the foreign income.
Guidance on what and when to report is at :
​​​Paying tax on the remittance basis (Self Assessment helpsheet HS264)