This episode (Glasgow UCOS) was postponed and the following episode Part of a Whole (2012) was shown in its place, because the storyline of Glasgow UCOS mentioned child abuse which was in the news at the time due to similar allegations concerning the late Jimmy Savile.
First episode in which Amanda Redman and Alun Armstrong failed to appear.
Since the pilot, they had been in every episode up until this one.
The trip from London to Glasgow can be made in one of three ways:
Car - Via the M6 in 6 hr 42 min
Train - Avanti West Coast from the London Euston Station in 5 hr 6 min
Plane - 1 hr 15 min
Information from Google maps.