Different countries interpret the McCarthy judgement differently. You may wish to check how they interpret it in your other country of citizenship.
But the UK rules are very clear. If you are a dual British/EU citizen, you are treated as solely British. So, your spouse would not qualify to apply for any EEA route permits in the UK, but must apply for a UK Immigration visa that is restricted only to the UK.
Glenhope is broadly correct. In order to use the Surinder Singh route, the EEA citizen must exercise treaty rights in a country of which they are not a citizen and while exercising treaty rights, also create or strengthen family life. If the creating or strengthening of family life takes place at a different time from the exercise of treaty rights, the Surinder Singh route does not exist.
So, for you to do the Surinder Singh route, you must do the following;
a) Move with your spouse to another EEA country of which you are not a citizen. That country is obliged to give your husband a visa provided he can prove that he is married to you and that he is traveling either with you or to be with you.
b) Once in this other EU country, exercise treaty rights.
Treaty rights start three months after you move to that country, so you must be there at least so long. The longer the better.
Exercising treaty rights means the EEA citizen doing one of four things in the host country
i) Working
ii) Seeking work
iii) studying (private health insurance is required for both of you)
iv) self-sufficiency (private health insurance is required for both of you)
If you plan to settle in the UK under the Surinder Singh route, the UK also requires you to prove that "the center of your life" had moved to this third EU country of which you are not a citizen. See the first post of
this thread to see the level of detail that is required to prove it.
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.