The pay and conditions agreement has hit repeated deadlocks and the final agreement was allowed to expire on 31 July.
The new APA guidelines make the UK commercials' production industry more competitive and aim to stem the flow of production to cheaper overseas markets.
According to Steve Davies, the chief executive of the APA: "There was no prospect of moving from the antiquated and inflexible union agreement, which gave rise to penalties at every turn, if we used it as the basis for negotiation.
"We therefore started with a blank sheet of paper and asked the question: 'What in 2002, is a fair basis for engaging crew on commercials?'"
The APA then sent its members recommended terms, which they in turn personalised to use with their crew.
Despite the union's failure to endorse the proposals, crews have accepted them and are working on the new basis.
The main changes include a ten-hour day on shoot days. This is based on the old eight-hour rate but no longer includes two hours overtime.
There are now no rest days on night shoots because the APA deems that paying crew at double time is sufficient.
Saturdays are to be treated as a normal working day, rather than being paid at double time, bringing the UK in line with foreign competitors.
Start times have been made more flexible. Work can now start between 7am and 11am which, with the longer shoot day, allows shooting through to 10pm without getting into overtime.
Travel arrangements have also been altered and crew can no longer charge for the first hour of travel in either direction. Mileage is now only payable to locations (not studios) and only then if it is more than 20 miles. Travel days are also to be subject to a minimum of five hours.
The APA is also aiming to promote the industry via screenings and events that it will take overseas. The first APA show took place at the Victoria & Albert Museum on Thursday 19 September.