Between season and certain episodes there will be specials to tell certain back stories of certain characters or even mini stories not long enough for a full episode for example The Tale of Master Fu (it tells his story of how he lost four Miraculous' and became the Guardian of the Miracle Box.) then You have The Age of Heroes special which shows Gabriel and Emilie back in their youth when Emilie was the Peacock Miraculous Holder and how she was a hero using Senti-Monsters to stop crime and save Paris how she fell for Gabriel worked as a Barista in the café Gabriel used to draw designs and eventually they fell in love and had Adrien & Felix.

So yeah they can range from 5 Minute episodes to 10 or even a bit longer. I don't really wanna restrict a episode my a time limit only by how long it takes to tell each story.

For your Audition for this Writer Role write a scene of either How Master Fu escaped the Temple of the Miraculous under attack with the Miracle Box or how Emilie & Gabriel met (either as Civilian and Hero or as just Gabriel and Emilie normal civilian attire)