I would have thought SEN would have gone the same way as STN and farmed it's radar service out to NATS at Swanwick
But the difference is that although the controllers are at Swanwick, they're still using the Stansted radar picture. Fine if everyone involved is NATS but I can't see that happening at Southend because the numbers just aren't big enough to justify it. Plus it would probably need a new radar at Southend anyway. What they might do at some point in the future is buy in a feed of SSR data from NATS (Debden or Stansted).
NS