@alan_mcbrien this setting actually does not retrospectively change existing invoice addresses. So if you set this option what it will do is exclude the client country from the address for any new invoices created. I tried this with a new invoice and it did exclude the country.
I had misunderstood the option - the client’s address does not show a country when same as mine, but Mr Ffinici here would also like my address to exclude the country when the same as the client - so that both addresses end at the postcode. I see that is not the purpose of this option, but perhaps this could be considered as an additional feature.