We do have our land across the road registered as available for quarantine, which covers showing. We had to prove that we could keep the two areas separate, and change boots and boiler suits, disinfect etc for each flock when quarantined sheep were in there. We used it for showing, as there is a 13 day standstill in Scotland, and all our local shows are on consecutive weekends. The re-registration is now automatic, although we no longer show. It is still useful for quarantining any new stock bought on (rare as we have a closed flock now)
So yes, speak to the movements folk for advice - they like to be helpful here, although I don't know about in the rest of Britain.