Phillip Schofield is in the Priory?

I'm not the biggest of Twitterers but I couldn't help be taken aback when I saw this Tweet from TV maestro and all-round Twitterer Philip Schofield a few minutes ago - http://twitter.com/Schofe

"Time to come clean. I must admit that I am currently in The Priory".

Is Gordon the Gopher's best mate having a laugh or is he serious?