Although this episode takes place during a single day, Boyce and Mac's hairstyles change from scene to scene.
During the course of the episode, various character's hair changes repeatedly, including Dr. Alan Statham's, Dr. 'Mac' Macartney's and Dr. Guillaume 'Guy' Secretan's which appears longer and shorter every so often.
When Rachel, Kim and Karen are sat outside eating lunch Karen mentions her friend having made her sandwiches. The satsuma segment in Kim's hand switches form one hand to the other without moving her hands (watch the bottom left hand side of the shot)
When Guy is handing Caroline his key, there is a moment when Caroline's green hair clip disappears from her hair during a close-up, but it then reappears seconds later.
When Martin is on the computer looking up what his old schoolmates had achieved, in one shot Boyce has his arm around him, in the next shot his arm is by his side.