The section of route between Edge Hill and South Parkway is mostly four-track with two intermediate stations at Mossley Hill and at West Allerton. Trains taking the CLC route through Warrington Central use it as well as those heading through Runcorn. The CLC line has (on the standard timetable), two stoppers per hour to Manchester Oxford Road, one fast to Manchester Airport, and the Norwich. The Runcorn line has the one London and two Birminghams per hour you mention. In the early morning there are extra trains to London, and equivalent early evening trains from London, both serving Liverpool demand and getting the stock from and to Edge Hill Depot for overnight servicing. The line is also the main access route for trains to/from Allerton Depot and before and after the peaks is busy with ECS workings between Allerton and Lime Street.
Well, unless you top & tail with locomotives (too expensive) or use a 37 with a DBSO on the other end as in Cumbria (too unreliable if the thread about that is anything to go by) or convert 68s/67s/DVTs/DBSOs to provide diesel push-pull trains (probably also too expensive) then it is probably true that there is nothing the W&B franchise could use. There are probably EMUs sat in sidings waiting for a TOC to lease them, but unless somebody manages to get Network Rail's High-Output OHLE Production train working as originally advertised (getting on for a mile or more a night wasn't it?) there won't be anywhere they can be used to release DMUs for the Halton curve service.
Oh dear. Better hope those 769s appear by December then. Otherwise somewhere else in the W&B franchise area will probably start seeing regular cancellations; there are already regular short-forms between Shrewsbury and Birmingham (4-car vice 6-car on the one or two services that were booked 6-car) as a result of PRM work and installation of retention toilets on the 158s I believe.
The additional 153s for W&B are not due until May 2019 if I recall correctly; hence my comments above that the 769s had better arrive soon. I think there are 5 class 156s due off-lease from ScotRail in December that currently have no home to go to, so in theroy the W&B franchise could take them on to cover for the late arrival of 769s, but as 156s don't form part of the medium-term plan I fear that is unlikely. Unless the 156s are owned by the same ROSCO as the 769s in which case maybe the 156s would be offered without additional leasing costs due to the late 769s?
Not to mention Merseyrail which stands to take the main hit.
With the current timetable there's a ~25 minute connection heading eastbound off the ex-Llandudno service, whereas the Holyheads are too late, or don't give a valid connection. Westbound there's a ~15 minute connection for the Holyhead service, or ~50 for the Llandudno. Connections for Wrexham are ~10 minutes southbound and 55 northbound. Obviously these issues will disappear when the through services are introduced in a few years' time.
The recently declassified ITT for the new franchise revealed that the DfT will only allow 1tph of "cross-border" services between Chester and Lime St in the W&B franchise.
