Billy Mitchell (EastEnders) revealed in 2006 that the role was extended by "coincidence and chance": "I was offered four episodes and here I am, about 800 later. [...] Ross Kemp (Grant) said that he was leaving, and there was a gap in the Mitchell family, so they brought me back to do stuff towards his leaving. After that they offered me a year." Billy was reintroduced in 1999, making recurring appearances. He was involved in the leaving storyline of Grant Mitchell in October 1999, before returning later in the year as a regular character. When Billy was first introduced, he was depicted as
Grant Mitchell (EastEnders) time on this ridiculous ending they could have made it a heart-wrenching farewell..." There were mixed reviews for the highly publicised storyline (dubbed "Get Johnny Week") involving the Mitchell brothers reunion in 2006. It was criticised as "patchy" and "awkwardly written... unveiling a common weakness in the "EastEnders" camp, that character continuity can often fall by the wayside when you are dealing with larger characters". Additionally, the show was criticised for turning the brothers into a comical farce by incorporating uncharacteristic humour into their dialect, which was described as "cringeworthy." Following Grant's third departure in September 2016, Kemp revealed that