I wonder if when new trains are ordered/in play, whether EMT (or whoever) will continue to run trains from Leeds to London or anywhere else.
Assuming that Neville Hill won't host the replacement fleet, I don't think there'll be any Leeds services from St Pancras Leicester etc (until CrayonistaRail introduce their Open Access service up the S&C anyhow...).
The nine coach 222s were ordered for that purpose, but that was in the days when Sheffield - Leeds only really had one service an hour better than the 1h10 stoppers via Castleford/ Dearne Valley.
Now, there's two semi-fast via Barnsley (okay, taking an hour to cover a route that's about forty miles as the crow flies isn't particularly fast, but these things are relative...
...plus there's be the two/three coach Northern Connect service (Nottingham - Bradford) before long that takes roughly as long as the hourly XC service, so I don't think there'll be so much room for a regular EMT service.
You could argue that an 802 each hour would be better than a 195, but...
Going back to the original question, it's likely that HSTs will be replaced. However I'd be surprised if Meridians are replaced
In these days where new stock is as cheap/cheaper than old (especially given that you don't need to have it away for months being upgraded to modern accessibility standards), I'd guess that they'll get one big fleet for the LDHS services - why keep two smallish fleets when you can get one bigger compatible fleet? The 222s are awkward lengths - they will find a home on XC.
The Government currently don't know what they'e doing next week let alone in 2033. A lot can change in the next fifteen years.
True - and lots of people want nationalisation (despite most of the industry problems being the fault of the Dft/ Civil Service/ Network Rail).
The other problem with 800s on the MML is the vehicle length. Two 5-car 222s can fit in St Pancras with a bit of extra length allowing them to be coupled and uncoupled in the platforms. But two 5-car 80x units would need about 20m more platform to do the same.
So it may be that an 80x solution ends up with all 10-car units, unless platforms can be extended at St Pancras (may be needed elsewhere too). A 10-car would be similar to the existing design with eight diesel engines and pantograph/transformers in both end cars but a 5-car would need design changes to put a diesel in one of the end cars so as to match the power:weight ratio. However 10-car would be over-provision on many off-peak workings.
The other issue is whether Beeston/ Long Eaton etc retain their current London service, and if so whether we need to keep relatively short trains on the MML. Could be a case of the tail wagging the dog?
I agree, a 395 type unit for Corby does seem complete overkill. It is a mid-distance commuter route for which a suitably specced Electrostar (or equivalent) is more than adequate
Rather than EMT ('s successor) having a small fleet of Electrostars (or equivalent), I'd give the Corby service to the GN franchise (depending on how TSGN is split, of course), since the same stock would be used on London - Cambridge/ Peterborough services.