An order for 24 additional trains with updated technology and a lightly revised design was placed in December 2016.

[4] As part of the PPP, Reliance Rail will also maintain the trains for a minimum of 30 years at the purpose-built Auburn Maintenance Centre facility.

[5] Reliance Rail took on debts of $2.4 billion at cheap interest rates before the global financial crisis.

[12] The inside of the train includes additional Emergency Help Points and CCTV cameras compared to older classes.

[16] The trains' exterior is of the same design and construction, but feature a different livery of black, orange and silver wrap applied to the cabs, and side windows.

The joint venture between Downer EDi Rail and Hitachi was established to design, manufacture and commission the A sets.

[4] The stainless steel bodies were partially constructed by CNR Changchun Railway Vehicles in China before being shipped to Downer EDI's Cardiff Locomotive Workshops facility in New South Wales for final assembly, testing and commissioning.

[4] Other infrastructure works included the construction of the Auburn Maintenance Centre and new substations at various locations around the network.

[25] CityRail had 20 business days to accept or reject the train, but a decision was postponed by two weeks to allow Downer EDi to correct further defects.

[27] The defects included; 'milky' effect windscreens – apparent when under direct sunlight, poor-quality steel welding as evident in the indents seen on some areas of the carriage exterior, gaps in the plastic moulding, handrails not lining up with stairs and software problems.

[9][28] Once the majority of the problems were resolved by Downer EDi, CityRail allowed A3 to commence service, though operating under special conditions.

[29] It entered service on 1 July 2011,[30] operating its maiden run from Redfern to Macarthur via the City Circle and Airport.

[54] Individual vehicles are numbered as follows: up to The first 40 A sets were delivered to CityRail with the NSW Government's Waratah logo on each carriage.

[citation needed] On 14 October 2014, set A29 was extensively damaged after it was trapped by rising flood at Bardwell Park, water reached up to the door level.

The cause of the incident was likely attributed to driver fatigue, and prompted a review of train crew rostering policies.

[59] On 22 January 2018, set A42 hit the buffers at the end of the track on platform 2 at an approximate speed of 35 kilometres per hour (22 mph) at Richmond station just before 10am.

The damage was such that the train could only be moved out of the platform after several days and it needed to be split into 2/3 carriage segments to be towed to Downer Rail at Cardiff.

[62] Set A42 has since been repaired and returned to service on 27 March 2019, with the driver carriage (D6342) that hit the stop buffer replaced with a spare from the prototype train (D6379).

[citation needed] On 5 September 2018, set A18 hit and killed a man at Riverwood while he was illegally on the tracks.

[citation needed] On 10 March 2023, carriage D6373 on set A73 suffered damage to its windscreen, destination screen and pantograph after bringing down power lines at Panania.

[64] On 25 January 2024, set A15 crashed into a trailer at Level Crossing Road at Vineyard, south of Windsor.

[67][68] In March 2020, a report from the Australian Strategic Policy Institute highlighted 82 companies directly or indirectly using Uyghur slave labour.

A spokesperson for Downer said the company had investigated serious allegations in early 2020, and that CRRC strongly denied the use of Uyghur labour.

[71] In October 2020, Premier of New South Wales Gladys Berejiklian stated that she was concerned over the possibility of Uyghur slave labour being used.