When the chaps make a stop for lunch in a pub on the way down to Margate, Vince tells Lenny'it's a quarter to two'. Later, once they reach Margate, they drive past a municipal clock, with the hands set at five-and-twenty to two (13:35).
The establishing shot of the hospital shows the sign for "Guy's and St Thomas Hospitals Trust" which was the name of the organisation when the film was made in 2001, but Guy's and St Thomas did not become a single NHS Trust until 1993, whereas this film is set in the winter between 1989 and 1990.
The fluffy head of the boom mic is visible at the top of the screen during one of the flashbacks to young Jack Dodds flirting with his wife-to-be (although at this point he has only just met her; they seem to be cutting runner beans, or something). This is visible even when displayed in the correct aspect ratio of 2.39:1.
When Vic first takes Jack in to the bar and orders a double whiskey, the publican, Bernie, pours two large drinks, but thereafter the amount of whiskey in Vic's glass halves and doubles between takes until the end of the scene.