1. I regret to say that it is a rule of UK Immigration law that a person holding British nationality and passport cannot use a different nationality in dealing with the UK HOme Office to attempt to achieve a more favourable outcome. Accordingly, that means that in this situation, you cannot use your partner/future spouse's Irish nationality to achieve a more favourable visa outcome. You must apply on the basis of your partner's UK citizenship. This is because it is a principle of British nationality law that a British citizen must use their British citizenship at all times when dealing with the UK authorities. They cannot chose or use a different nationality for a more favourable outcome.
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