The FCDO (Foreign, Commonwealth and Development Office) are advising against travel to where I am due to stay, is this covered?

There would be no cover for any costs incurred in the region or country if the FCDO are advising against travelling there. If the FCDO are advising against all but essential travel to that region/country, you would be covered if you needed medical treatment for an injury or some other illness, but not for Covid-19.