Factual error: After Jim escapes the house and makes his way back to the blockade there is a shot of him operating the siren. In the background is a sign saying that the M55 junction for Blackpool is in 1/3 mile. The M55 is nowhere near the M602, where the blockade is supposed to be. (01:30:20)
Factual error: In the scene on the motorway where we see Manchester burning, the road signs are for the A421 and A507, which are at M1 junction 13 near Milton Keynes and nowhere near Manchester.
Factual error: After they leave Jim's parents' house Jim and Selena are seen walking through Canary Wharf, but they're coming from the wrong direction. The Docklands Light Railway tracks that they use to cross the river are in front of them and their base (in Canary Wharf Tube station) is even further in front of them. Why did they cross back over the river and then walk away from the safety of their base? (00:29:00)
Factual error: The film states that the 42nd blockade is located on the M602 motorway, 27 miles outside of Manchester. The M602 is 3.4 miles away from Manchester at its farthest point and is barely three miles in total. It is a very short motorway. It only has 3 junctions. The filming location was actually the M1, outside Milton Keynes.
Factual error: In the scenes driving to Manchester the motorway is completely clear of traffic, no abandoned vehicles of any sort. With an outbreak like this happening the motorway would be gridlocked.