Although the action develops during a month or so, Spector's daughter, Olive, is visibly getting older from one season to the other.
Early in the series, Burns tells Stella that he's riding in a reinforced car in keeping with the dangerous climate in Belfast. Later, when Ferrington approaches to tell Burns and Stella about the Peter Piper development, Burns lowers the rear window, which wouldn't normally be possible in an armored vehicle.
Throughout the series, the same standard 1980s/early 1990s audio sample can be heard any time a character uses a computer mouse, though the devices shown on screen are modern, optical mice, which produce a distinctly less mechanical sound.