In the forces, we get council tax breaks....you get a pecentage off for the time you are serving away from the UK...but it is nothing really...
also, to top that up..if you live in barracks, you have to pay council tax in lieu (which is a small fee) regardless of the fact you pay CT at your home address.
in short, if you are away from the UK for 6 months, you get something like 2 months counil tax free when you work out your savings (or something very similar)...you have to claim for it when you get back..which again, turns out to be its own epic