In October 2016, four offers were selected for the next franchise in Wales – Borders: Abellio, the incumbent operator Arriva, a joint venture Keolis/Amey and MTR Corporation.   In 2019 and 2020, some units in the 170 series and many other units in the 153 series were purchased by some English operators to expand the fleet. They work next door and with ex-ATW units, increase capacity and support new services. In addition to the all-new fleet, the 12,170 will be maintained for the duration of the franchise, but will serve various routes, including the West Wales, Shrewsbury-Crewe and Heart of Wales lines (which depends on the units being released for operation on it). A total of 77 Civity series 197 diesel units were ordered from CAF for long-distance lines. These trains will have terminations, but will replace fewer toilets than the 158-series and the 175 DMUs class.  However, they will be faster, with more powerful engines and more efficient gears for higher acceleration and maximum speed than the 158. The rest of TfW Rail`s rolling stock (series 150, 153, 158 and 175 DMUs), which will be removed and replaced by 2023 (with the exception of the 153 “short-term” series that were withdrawn earlier) will be making several changes. These include the application of the “Transport for Wales” paint and the interior renovation of the TfW Rail specification (including the new seat carpet, flooring and table surfaces, as well as ac and USB sockets). [Citation required] In addition, the remaining 150s/153s/158s until 2022/23 receive modifications to the STI PRM (REDUCED MOBILITY – Technical Interoperability Specifications) (the 175 exceed the RVAR on which they were built and are accepted without modification). Six 67-series locomotives have been adapted for work with three sets of four 4-mark cars each and a Mark 4 Driving Van Trailer, which replaces the Mark 3 storage extension previously used for locomotives.
The 12 cars and three DVTs were deceded from the London North Eastern Railway due to the launch of the Class 800 on the East Coast Main Line. The review and training of these kits began on January 28, 2020, but it is not yet known when they will be commissioned. The Mark 4 buses retain the paint from the east coast of Virgin Trains, but with transport tags for Wales. The “Mark 4 Driving Van Trailer” is painted in the new painting “Transport for Wales”. Four of the six 67-series locomotives have been repainted in tfW. Amey Keolis Infrastructure / Seilwaith Amey Keolis Limited (AKI) is the infrastructure manager and will provide asset management services to Core Valley Lines (CVL) on behalf of KAWCL. AKI will provide management and maintenance of CVL`s infrastructure and resources.