With regards to this "project" (in the loosest possible term) - a certain pair of Northern Mayors are attempting to drive this forwards, moreso than GBR/DfT.
Good political opportunity to spin here - "new" and fairly nice trains laid up in sidings with no prospects, whilst telling the story that Merseyside and Greater Manchester otherwise continue to get ancient and well worn castoffs from BR days.
Levelling up etc. If that coincides with a ROSCO offering a good financial incentive, moreso the better, especially as the ultimate asset owners of the 323s will not want to sink huge amounts of money in increasingly difficult to maintain rolling stock, particularly the ability to obtain parts.
Bringing "new" trains to Northern may well solve a few issues both politically and mechanically - so long as the timetable isn't (too adversely) affected. No doubt an introduction could even coincide with the run up to an opportune election or bad news day.