Dom is shown working on a building site where he is working with his father and Bex arrives dressed in a suit. Dom is seen passing wood materials through a open window to his father as they all talk. When Bex leaves, Dom's father is seen passing the same stacked wood back across to him which we seen him already stack.
They boys are seen at various times going into JD Sports, the film is set in 1983, JD Sports didn't open a shop in London until 1989.
Towards the end of the film Bex and the rest of the firm are seen going into a London underground station and through some very modern looking ticket barriers.
When the hooligans arrive in Portsmouth, automatic door locking lights can be seen on the side of the train cars (the blue and white livery is correct though) - automatic train door locks were not introduced until 20 years later. Also, the locomotive pulling the train is sporting WEST COAST RAIL colors which were not around until 2004.
The main characters Bex and Dom are seen sat inside of a white 'scaffolding' van and visibly seen on the van's interior by the passenger seat belt is a modern L.E.D touch light gadget. This typical modern technology was not developed during the decade in which the film is set.