Has TfW ordered enough 197s or it will the remaining units when in service make up for the capacity shortfall? I would not be happy if a 3/4 car 175 became a 2 car 197.
Long term the plan is to run a lot more multiple sets either 2+2 or 2+3.
It's difficult to balance the numbers for TFW as there's been so many changes of late.
The majority of the fleet would have been 158s (24) and 175s (27) along with a number of 150/153's on West Wales, Bidston, Crewe - Shrewsbury and Crewe - Chester to name a few. If you include the 153's (26 - so 13 pairs) that's 64 units vs CAF's 77.
Bear in mind that 153's will be retained for West Wales and HOWL services.
Also throw what was originally planned to be 8 Mk4's, now 7 with a maximum of 5 in service which eventually will be 5 carriages. That's 82 sets for Mainline work.
This excludes where the 231's will be deployed (Maesteg, Cheltenham, Ebbw Vale). I wouldn't be surprised to see them on Cardiff - Swansea Swanline services too.
Then when you take into account SDs analysis that there will be 26 3 car 197's vs 16 3 car 175's, overall carriage capacity will be increased across the board.
The attached photo is from the Franchise proposal of where the fleet would be. Things have changed a lot since then.
The 175's should have gone by Q2 2022
The 158's should have gone by Q1 2023
The 153's should have gone by Q1 2023 (Now staying to replace 170's)
The 150's should have gone by Q4 2023