The above also applies to civil partners who have the same rights as spouses. Civil partnership is a registered partnership between the 2 people of the same gender, such as 2 men or 2 women. If you are a man and a woman but not married then you would be unmarried partners (subject to the above 2 year rule) and not civil partners. If you are 2 men or 2 women but have not registered a civil partnership then you would be same-sex partners, which is the same category as for unmarried partners and have the same conditions as in the option 1) above.
Then the same: 2.5 year visa, then extension for another 2.5 years and then permanent residency.
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