Several cast members appeared in the radio comedy panel game "I'm Sorry I Haven't a Clue", a spinoff from "ISIRTA" that has outlived it by decades. Graeme Garden and Tim Brooke-Taylor continued as regulars on the show. All series of "ISIRTA" have been rebroadcast on BBC Radio 4 Extra (available on digital television, DAB digital radio and the web), though some episodes (series 8 episode 2, and series 9 episodes 5 & 6) were not transmitted due to potentially offensive content. Listeners in Australia occasionally find "ISIRTA" in the 5.30am vintage comedy timeslot on ABC Radio National (available on the web to overseas listeners). In 2015, plans were announced for a live "Best Of" homage show, using material by Garden and Oddie, and performed by Hannah Boydell, David Clarke, Barnaby Eaton-Jones, William KV Browne and Ben Perkins. The show was a sell-out success at The Bacon Theatre, Cheltenham in February 2016 and a tour was licensed by Graeme Garden and Bill Oddie to the same company, the Offstage Theatre Group. In February 2017, it was announced that the British tour would take place later in the year, with guest appearances by Garden, Oddie and Jo Kendall. In 2019 three new episodes with the slightly modified title "I'm Sorry I'll Read That Again... Again" were recorded and broadcast on Radio 4 Extra with some original cast including Tim Brooke Taylor, together with newer performers such as Barnaby Eaton-Jones. The episode titles (for shows from series 3 onwards) are unofficial and mostly come from the last sketch in each episode, which usually took the form of a short play. Figures in parentheses after each title are the Series and Episode numbers, where known. For example, '(S9E7)' refers to Series 9 Episode 7. Writers and cast in order of appearance:  Comedy songs replaced traditional songs during episodes. "ISIRTA" is referenced in The Goodies's episode "Chubbie Chumps", where the initials are printed on the wall in chalk. "Spot the dog" is referenced in The Goodies's episode "Camelot" as the royal dog "Spot", where it received an immediate cheer. In the computer game , there is a magic spell called Kendall, found just before a reference to a magic plane shared with people who own ferrets.