Scotland has already pledged to be rid of diesel passenger trains by 2035 with most of their electrification to be done by then and all bar the West Highland due to eventually have a signficant portion under the wires. So they won't need any of the Civity DMUs, and neither will Anglia thanks to their FLIRTs. The only routes on the TDNS map where a Civity DMU could run without wasting investment in electrification by running under the wires for a substantial part of the trip are:
- Newport - Ebbw Vale (Cardiff - Ebbw Vale has more under-wires running)
- Conwy Valley Line
- Wrexham Central - Bidston
- Oxenholme - Windermere (if you don't ru
- Looe, Falmouth, Gunnislake and St. Ives branches
- Henley and Marlow Branches (assuming no through running onto the GWML)
- Middlesborough - Whitby
- Darlington - Bishop Auckland
Based on
this topic, that's about 22 units in service daily. Everything else really ought to be able to draw power from OHLE and/or third rail and even then I get nowhere near 161 self-powered units. Admittedly that's the end game and we've a long way to go before we get there, but if we want to decarbonise rail by 2050 with a steady rate of electrification we are looking like having a surplus of diesel units sometime after 2040.