There was a thread a few years ago about this and what actually happened. For some reason I can’t quite the relevant bit directly, but I can copy it:
Interesting to look back at what was planned at the beginning of the Arriva franchise. Their website said that "Northern Connect will be a new network of 12 long distance routes. To be introduced in 2019, it will provide faster connections across Northern England to Leeds, Liverpool, Manchester, Newcastle and Sheffield, including brand new services from Bradford to Manchester Airport and Lincoln to Leeds."
So what's happened?
1. Manchester Airport to Barrow (new build dmu) - in operation
2. Manchester Airport to Blackpool/Windermere (new build emu) - in operation but Windermere is new build DMU
3. Manchester Airport to Liverpool via Warrington Central (new build dmu) - in operation
4. Chester to Leeds via Warrington BQ, MCV, Calder Valley and Bradford (new build dmu) - in operation
5. Liverpool to Leeds via MCV, Calder Valley and Bradford (new build dmu) - not happened
6. Manchester Airport to Leeds via Calder Valley and Bradford (new build dmu) - not happened, runs from Victoria only
7. Leeds to Lincoln via Barnsley and Sheffield (new build dmu) - in operation
8. Sheffield to Scarborough via Doncaster and Hull (new build dmu) - in operation but using class 170 units
9. Middlesbrough to Newcastle (refurb. 158) - not happened, this was to have been a service via Durham and Stockton, not the coast line
10. Newcastle to Carlisle (refurbished 158) - in operation (actually from Morpeth)
11. York to Blackpool via Leeds and Calder Valley (new build dmu) - in operation
12. Bradford to Nottingham via Leeds, Wakefield Westgate and Sheffield (new build dmu) - in operation, but not from Bradford, and via Barnsley
Route 3 is a part replacement for TPE, which will no longer use the CLC route
Route 4 ditto between Warrington and Leeds - BUT route 4 is an all-stations "stopper" between Leeds and Todmorden!
Eight of the 12 services are therefore operating as planned, two of them not with the intended type of unit (one because of cancelled electrification). One other is running in a modified form while three have not been implemented, two because of capacity problems through Manchester.