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The drawing both Kenny (Alex Lawther) and Hector (Jerome Flynn) receive at the end of the episode on their cellphones is a popular meme called Trollface, which is used when someone has "trolled" anyone else (which means pulling a prank or a joke). But "trolled" can also mean to control, which is basically what Kenny and Hector suffer, being controlled during the entire episode just to end up suffering a heavy prank.
This is the first episode since episode 1.1, The National Anthem (2011), to only feature currently existing technology.
The news site browsed by the CEO at the end of the episode mentions Michael Callow (Rory Kinnear)'s impending divorce (episode 1.1, The National Anthem (2011)), Victoria Skillane (Lenora Crichlow)'s trial (episode 2.2 White Bear (2013)) and an advertisement for 'cookies' (episode 2.4 White Christmas (2014)). There is also a banner item for a new TV show, 15 Million Merits (episode 1.2 Fifteen Million Merits (2011)).
The price of the fuel was almost the same as the credit card's PIN (different in one digit) that led Kenny (Alex Lawther) to input it incorrectly.
In a reference to episode 2.4, White Christmas (2014), the restaurant Kenny (Alex Lawther) works at is 'Barnies' which was listed as part of Greta (Oona Chaplin)'s schedule.