Behind the scenes
- Coburn shares their first initial with Waris Hussein and their surname with Anthony Coburn, the director and writer respectively of the first ever Doctor Who story, An Unearthly Child. These references were included in The Day of the Doctor to further celebrate the programme's 50th anniversary.
- They also share their name with the in-universe character Wendy Coburn from Time and Relative, who was a pupil at Coal Hill in 1963. Later reference to the headmaster as a male, however, establishes them as two different characters, though Clara may have been referring to Mr Armitage.