Caravel88 wrote: ↑Tue Jul 31, 2018 9:47 am
Guernsey is not part of the UK.
It is much more complex and nuanced than that.
The Channel Islands and the Isle of Man are Crown Dependencies and some Acts of Parliament apply to them. So, each of the various Crown Dependency (Guernsey, Jersey, Isle of Man, etc) have their own Immigration Rules and they are not a part of the EU for the purpose of freedom of movement. But the British Nationality Act 1981 does apply to them and a person who naturalises there becomes a British citizen, though their naturalisation certificate will be issued in the name of the relevant Lieutenant General, not the SSHD and
their passport looks different compared to the standard British passport. But they are British citizens nonetheless.
To the OP, the Investor visa does lead upto ILR in Guernsey. See
Guernsey Immigration Rules 224-231 for details. I do not believe that the ILR is portable i.e. it allows for residence in Guernsey only, though of course you can travel to and from the UK.
You should then be able to apply for naturalisation and a British passport in the usual way.
I am not a lawyer or immigration advisor. My statements/comments do not constitute legal advice. E&OE. Please do not PM me for advice.