I think that what ever new Rolling Stock is Built it will still only be two Car Units when in this day and age we need at least 3car DMUs.
And it is about time that they Stopped this business of only two carriage units along with the Railways need to be brought out of this time-warp which it is still in with no thanks to DfT.
The spec has called for two and either three or four carriage units.
It's a shame we can't just build "generic" middle cars to add extra capacity into a DMU - much better than running doubled up units with no corridor connection.
It won't help in the short term, but the spec requires corridor connection between units too.