Referees who recently moved to Guernsey

Hello!
We are hoping to apply for the UK citizenship. I read here and on gov.uk about reference letters, who can be referees etc. I have a friend who qualifies based on her profession. She has worked in UK for a few years. And her husband fits as a UK citizen (holds UK passport). So I had them in mind.
But a month ago or so they moved to Guernsey, Channel Islands. We are planning to apply for citizenship at the end of June.
I am wondering can I still use them as referees?
The referees need to provide their addresses for 3 years. And Guernsey is a British Crown dependency.So I am thinking probably it is ok?

As far as I know that should be ok - as Guernsey is a dependency.

The Channel Islands are a part of the UK for the purpose of nationality law (though not for the purposes of other laws). So, you should be fine.

Be aware that the two referees can't be related to each other or to you. So you will be able to use one of them as your referee, not both.

Thank you for your answers. And thanks for flagging that the referees shouldn't be related! I will manage find the British citizen as a referee but finding a professional one is tricky.