The EU Succession law uses the place of habitual residence of the deceased as the default rule for determining applicable succession law. However, this may be “overridden” by electing for the law of nationality to apply.
Such an election would be a factor in determining the domicile status of an individual for UK tax purposes but would by no means be a sole determinant.
Many non-UK domicilaries retain their British citizenship and have UK wills but their non-UK domicile status persists.
Malcolm Finney