The need of a domicile applies on you only in the condition that you own foreign income or gains during a tax year. This type of income comes under income tax or capital gains tax,but, if you did not gain any foreign income during the reporting period, you do not need to be concerned about it. Obviously, your domicile status has no effect on UK income tax system.
On the other hand, UK’s overseas tax verification area is a vast subject. Intense examination on the applicant’s background over the period will be checked before any decision is made.
The HMRC rarely checks one’s claim to be domiciled in the UK. If you say you are non-domicile in the UK, the HMRC will especially check such authenticity. In case of claim of a UK based birth, the HMRC will especially check the authenticity.