Continuity mistake: When Lennox Gilbey opens a can of beer in the supermarket, you can see that he has a long packet of spaghetti inside his jacket. He doesn't take it off the shelf until a few shots later. (00:06:00)
Continuity mistake: When Tom is talking to the Trotters, the lid on the washing up liquid keeps changing between open and closed. (00:01:30)
Continuity mistake: When Albert walks out the store at the start he has a box of shopping. When he gets to the manager's office, the position of items in the box has changed. (00:05:20)
Continuity mistake: The colour of the toilet rolls changes from pink to green while in the office. (00:06:15 - 00:17:40)
Visible crew/equipment: When Uncle Albert walks round the corner to the manager's office, a camera shadow is seen on his coat. (00:02:20)
Plot hole: The Trotter's are taken to the office while the supermarket is still open, the office containing the safe. Tender pickups in supermarkets are done throughout the day but how did the cash from the tills at closing reach the safe? It is unlikely that a supermarket would leave large amounts of cash in tills and counter caches. The Trotters were actually in the office as the store closed, as well as Lennox. The safe is far too small. A safe in a large supermarket would contain large bags of change and would have an inner safe for cash bricks. Also, how is it that no other member of staff noticed the situation in the office - such as maybe a member of staff involved in cashing-up tills needing to gain access to the safe? (I work in a supermarket as a Duty Manager).
Chosen answer: An apparent long string of illnesses.