Last time I got there Sainsburrys processed it for the next morning 5.25 for a 36p on a cd not so expensive.
Jessops on my experience mayu have really bad and dirty chemicals...

But be happy you can still find local people to process it fast. I'm back in France and eager to grab a C41 kit as I can only hope recieving my films in the 8 days after putting them on the desk more for slide or BW (happily I still have E6 and BW chemistry...)