[7] At the time, the operator had completed a life-extending refurbishment on its existing fleet that was intended to take it up to its planned life-expiry date, which was estimated for the early to mid 2020s.

[10] In September 2020, Nexus undertook a second public consultation to ask for opinions on how the interior of the new trains should be designed, related to the seating, grab poles and space for bike racks.

Unlike the previous fleet, which had only a half-width driver's cab at each end, with the other half occupied by passenger seating, the new units will have a full-width driving position.

They will have an overall capacity of 600 persons, with 104 seats,[11] specially designed easy access areas and have CCTV, a new passenger information system, USB charging points and air conditioning throughout the saloon.

In December 2021, Nexus revealed that the Metro fleet had entered the final assembly phase at Stadler's factory in Switzerland and that the manufacturer is in the process of fitting the main interior components of the first of the new trains.

The works include the installation of wheels, seats, equipment cases, piping, wiring, flooring, windows and other internal furnishings.

[12] The first of the 46 units, costing £362 million, arrived in Tyneside on 28 February 2023, and will undergo compatibility testing across the network before entering into service in the Autumn.

[16] Cathy Massarella, Nexus's major projects director said to the BBC: "[The] train has completed its first test run out on the network and performed really well".