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All the Nuc does is unlock your phone so that any network sim card works in it.
It does not affect your Vodafone sim card.
Current Phone > Samsung Note 10+ 5G _256Gb > Model: SM-N976B.
Samsung One Ui / Pie.
Samsung Gear s3 Frontier Watch.
Just to be absolutely clear, as I'm a belt and braces person, once I have unlocked my iPhone 4 I will be able to use it on 2 different networks by just swapping over the 2 sim cards?