Far as I know Andy, both the '410 and the '190, both now static display pieces, at Cosford and Hendon respectively, have been kept in serviceable condition, with the engines correctly inhibited. Certainly the '410, when I got the photos for you, was undergoing service, to maintain not just the airframe, but the systems too.
Whether they'll ever actually be run again, I don't know. The RAF Museum(s) have a policy of maintaining airframes, at least, in the best possible condition for future generations, and rotate aircraft as required in order to do this. The Wellington, from Hendon, for example, is currently undergoing further restoration and renovation at Cosford, and the Bf109G, now on permanent static display at Hendon, was placed there after an agreed, limited period of airworthy, flying display.