Don’t think it’s safe to assume anything like that anymore. There is the precedence of the unexpected mass extinctions on Anglia and SWT, the unknown future of franchises, and a government wanting to shore up its support (and XC is shiny Express trains that don’t serve London.....)
The slight difference with Anglia is that the 321s would have needed a substantial rebuild to be suitable for service post-2020 (from the PRM angle) and it wasn't worth the investment. There is not a 'push factor' on the 220/221/222 fleet from the PRM angle. I agree that there is an issue with the power source but a lot of the route doesn't have an agreed schedule for being electrified yet. Extra 22x forms a readily available stop gap.
The 222s are coming from an electrification project. Cascading the 222s to XC means that the amount of diesel units in service will remain the same overall. With electrics being introduced on EMR the proportion of diesel running on the network goes down. I bet this will be projected as decarbonising. Cynical? You bet!
4-7 cars long. 7 cars is the perfect length for XC, enough capacity for growth but not so much that you are needlessly taking around a couple extra carriages. To be honest I wouldn't be suprised if they scrap some of the cab cars in stick the intermediates in other sets to extend them. There isn't enough operators for all the 220s, 221s, and 222s so using the middle cars to extend some of the sets would make the most sense.
Does that not assume a level of compatibility that just isn't there between 220/221 and 222?
LO 378s...
a few battery cars are getting into a few 331s to turn them from 3 cars to battery 4 cars.
The incompatibility thing is often cited, but in theory it isn't a show-stopper. Am I right in thinking that the main obstacle is to do with software? If so, that really ought to be relatively simple to solve. After all, Grand Central and others (including XC IIRC) had loco-hauled mk3s rewired to take HST hotel power, and those vehicles were around the same age as the 22x fleet is now.
As l understand it the 220/221s had an Alsthom TMS installed for improved compatibility with Virgin's Pendlini. I'm unsure if the differences are solely software or if there is hardware involved too.
I appreciate the correction and comments. Though that's the thing with software- it should be simple to upgrade or modify or replace, doesn't necessarily mean it will be. But as with so many things, if you throw enough money and expertise at a problem like this, it really ought to be soluble. How much money and expertise would be needed, and whether that expense and time is worth it, is of course another thing altogether.
The last para sounds about right... Not something HMT are famous for doing though....I appreciate the correction and comments. Though that's the thing with software- it should be simple to upgrade or modify or replace, doesn't necessarily mean it will be. But as with so many things, if you throw enough money and expertise at a problem like this, it really ought to be soluble. How much money and expertise would be needed, and whether that expense and time is worth it, is of course another thing altogether.
The problem with online fora is that it isn't always easy to get across the subtleties of what you're trying to say- I've worked through enough system upgrades to know that they aren't as simple as you think they'll be, and that anything that can go wrong will go wrong somewhere... especially if the people working with the system through the upgrade aren't the people who designed it. My point was that these things ought to be relatively simple, not that they are in fact simple. On paper, you'd decide which TMS is superior and install that system across the fleet, but i appreciate that's a deliberate oversimplification and there's plenty of issues that could throw up.
Ultimately it comes down to £££ though: pretty much any problem is soluble if you throw enough money at it... particularly if it isn't your money!