If the timetable stays the same, Northern will need 12 electric diagrams for the existing Manchester/Warrington/Wigan services.
I doubt they would want to diagram the other 2 units while fleet experience is building.
Some of the services could be sped up by 5 minutes or so, and maybe the Victoria service could manage with one unit fewer, with a fast turnround.
But whether that sort of change is envisaged this side of the Bolton electrification I don't know.
There are a few peak Liverpool-Preston workings which could go electric, but they are currently linked to the Blackpool services.
I think 12 diagrams would need some very tight turnrounds, and leaves potential for poor timekeeping, particularly as they also have to make paths available for TPE services on the Chat Moss route. Unless they reduce "charter time", I think that Liverpool / Wigan and Liverpool/Manchester journey times may only be 2 -3 minutes faster at most.
So, ideally they probably need something like:-
Liverpool - Manchester Airport (hourly) : 3 units (as now)
Liverpool - Mancheter Victoria (2 per hour) : 5 units
Liverpool - Wigan (2 per hour) : 5 units
Plus, eventually:
Liverpool - Preston (hourly) : 3 units, becoming 4 units when they extend to Blackpool, or 5 units if they retain the lightly used Lime Street / South Parkway extension of the Blackpool/Preston services.