Continuity mistake: In the sketch with the Prime Minister, when Sebastian brings over the chocolate fingers, a shot before he brings them over there is nothing on the table. When Sebastian puts them on the table suddenly a cup has appeared. He did not bring over a cup and put it on the table, just the plate.
Continuity mistake: In the sketch with Kenny Craig, just after his mother brings in the sugar, the pot of sugar is quite close to the cups of tea. However in the next shot when Kenny hypnotises her and makes her not watch Songs of Praise, the sugar pot is now further away from the cups of tea.
Continuity mistake: In the first Andy and Lou sketch, when Andy sees the intro to 'The Price Is Right', there is a cup in front of him. However in the next shot Lou brings one over and it is the same one in the same position as in the first shot. Obviously the second shot was filmed first.
Deliberate mistake: Andy is watching TV, when Bruce (presenter of Bruce's price is right) is calling out for contestants he shouts out three names (Helen Hunt, Akshai Vikoria and Andy Pipkin). However, when we see the contestants - there are four and Bruce says "You are the first four contestants on the price is right" even though only three people were called out. (00:06:55)
Revealing mistake: Just before Andy pushes Francesca down the stairs in her wheelchair, we see Lou walking down the steps, and they are quite steep. However, when Francesca goes down the stairs in her wheelchair she doesn't have much of a bumpy ride, despite the steps. A ramp was put there - you may need to look very carefully and you see it pop up slightly from the steps. [A reasonable way to prevent injury but it is still a mistake.]