The original pilot was broadcast in 1973 as part of BBC1's 7 of 1, a series of potential pilots showcasing Ronnie Barker. (Seven Of One featured one other pilot which was eventually made into a series; Porridge). When the series was properly made and shown (in 1976), there were a few small changes, including a different actress playing Nurse Gladys Emanuel and a different location for the shop.
When Ronnie Barker first saw the script, the character of Arkwright did not have a stutter. Barker always credits Glenn Melvyn as the inspiration for the stutter.