Hmmm... I renewed ours not long ago. Photos are your responsibility, you need to get the taken and witnessed by having someone sign the back. Details of who can witness are on the application form. From memory, you still need to eat your application for renewal witnessed as well. The appointment at the post office is pretty straightforward, you just need to take ID with you. I did app,y for DD2's passport at the same time so a bit hazy on what was for a new passport and what was for renewal!! It was not difficult, and all explained on the form.

Eta Zazou didn't he have to have the photos witnessed? I'm sure we did...