XD816 was a 214 Sqdn a/c. In GeeRams picture the 214 loggo on the fin is quite clear. Also visible on the black painted section of the nose are the Rebecca Mk X shark fin aerials. We used to tell visitors that they were a 'sight' to aid the inflight refuelling!
It spent a lot of time as the 'test bed' for Flight Refuelling to fit the 1st bomb bay mounted Hose Drum Unit.
Because of this time as a 'hanger queen', its hours and cycles were low, and someone decided to keep and use it.
After the scrapping of the rest of the Valiant's, XD816 spent time at Boscombe. I dunno what they used it for.