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"Up All Night" couldn't be used as the theme tune for the series due to rights issues so instead the stories opened using the 'Class Credits' music, that had been composed by Blair Mowat to play over the closing credits of the TV stories.
Because the licence was acquired before the show's cancellation, the audio stories for Volume One through Volume Four couldn't develop the cliffhanger of the first series' final episode The Lost, as they might have created a conflict with a potential second series, which never came to be. Thus, as of 2020, all stories being developed for this series needed to take place between the events of the show's first series.Queen of Rhodia, capping off Volume Four, takes place furthest along the timeline, between The Metaphysical Engine, or What Quill Did and The Lost.
Both 2018 volumes were first announced in DWM 526; individuals whose copies arrived early leaked the news to social media. That same day, Greg Austin posted on his Twitter about working with Big Finish. As the news broke, the series did not yet have a page on the Big Finish website.
Scott Handcock was approached by Nicholas Briggs about making audio stories for Class around the time the first series premiered, as he had gotten a licence for it. However, due to scheduling and developing of the storylines, it took a while for the stories to actually go through and get recorded.
The physical copies of Volume One and Volume Two had a slightly wider cover than the digital version, so that the illustrations formed a single image when put side-by-side.