Yes, Swinton, although Swindon is being done too, so technically via Wigan, the WLL and Reading, it will be electrified to Swindon...
Well, since the Bolton route wouldn't have enough capacity with 3 car 323s or 4 car 319s on a few services (namely those to Piccadilly / Oxford Road) I think we've just found the allocation for the 323 units...
319s can work the new S Manc lines and the services via Bolton into Victoria, but seriously for a moment, there isn't that much difference between a 3 car 323 and 4 car 319, the major difference is between a 319 and 2x323, the latter being needed on a lot of Bolton peaks, where as a 4 car 319 (with comparable running costs) would do nice all day on the Atherton Loop and the Southport runs (although too long for a couple of plarforms on the way there, lengthening could be done easily enough)
If this where to happen though, it's all the more reason to not split the 319 fleet up and either send them all to Northern or all to Great Western, especially if you implement another NW electrification programme covering another set of routes out of Manchester...
The 'Chinley Electrification Plan' I came up with before...
Hazel Grove - Chinley Electrification, extend Hazel Grove services to Chinley
Guide Bridge - Chinley
Romiley - Rose Hill Marple (Possibly re-opening the route to Macclesfeild, take some pressure off Stockport and provide an LDPE diversionary route for when HS2 works need doing, additional bays at Manchester Piccadilly East may be needed, as well as Guide Bridge - Ardwick 4 track)
Ashburys - Romiley
Then...
Anything that terminates at Marple or Rose Hill Marple continues to do so, services to New Mills Central continue onwards and terminate at Chinley
So that there will be 1tph via Stockport to Chinley and 1tph via Romiley to Chinley.
Services to Sheffeild would remain the same for LDPE services, 1tph EMT and 1tph TPE, via Stockport.
None would need to call at Chinley thanks to the regular Hazel Grove service, although some could to provide better links between Chinley and Sheffeild.
The stopper through the Hope Valley goes hourly, and between Chinley and Manchester only calls at Chinley, Guide Bridge and Piccadilly
Possibly extend one of the Marple terminators to Chinley, replace the bays at Chinley for these services to terminate.
Wires initally would end at Chinley.
If the line to Matlock is re-opened, services via Matlock would call at Chinley only and then onwards to Piccadilly in the same fassion as the Hope Valley services, running fast from Chinley to Piccadilly / Victoria.
That would kick out a fair few more pacers, and if combined with the TPE electrification, displacing 185s (as I wanted to happen) onto the Buxton - Piccadilly route, some calling patterns would change.
The Hazel Grove service could go half hourly all extended to Chinley, Chinley would have 2tph via Romiley and 2tph via Stockport stoppers, Buxton - Manchester is sped up so that between Hazel Grove and Manchester, it calls only at Hazel Grove, Stockport and Piccadilly, this would be re-cast to replace the current TPE service over the CLC as the timing to arrive into Piccadilly, running as the xx07 to Liverpool Lime St via CLC, meaning the CLC retains it's two semi fast services, and confilicts are minimal as they can run the approaches into Piccadilly on the slows from Stockport, flighted infront of a slow service (from Hazel Grove or Crewe, that will cover the stops at Levenshume and Heaton chapel) no diesel services running stoppers, in Greater Manchester, Anywhere, except!: Rochdale (Should be done to Rochdale with a turnback to push services through Victoria) and Chester via Alty, but the latter should get taken care of by Tram-Trains into a re-built Oxford Road via Sale.
Atherton Loop, Southport, Lostock - Wigan, Kirby, East Manchester Lines and Mid Cheshire TramTrains would be a massive policical positive move, get rid of a shed tonne of pacers, about 40 - 45ish, provide an increase in capacity where it is so desprately needed in the GM Travel to Work Area, and if new stock is gotten for these schemes (3x23m long EMUs and 4x23m EMUs) be a step increase in the quality of rolling stock in all of the north, (if there is a massive order of these EMUs for TPE and Northern (100+ units) the price should come down, and the 323s can be send down to LM for the XC Lines to get extras on there)
If the Valley Lines are completed aswell, (Thats up to the WAG) then thats pacers effectively gone, and general public opinion of the railway in areas where it is starting to suffer, gotten back, "Oh look, shiney new train is twice as long as it used to be and I don't stop everywhere on the way into Manchester any more."
And the 86 Class 319 units can have a gentler early retirement on the GW, go through a full refurb on a moving cycle and run crowdbuster services into Paddington at 12 or even 16 cars long from Newbury, Oxford, Didcot and Reading. Passengers get on the HSTs rather than what will be crossrail because of speed, if you knock together a 16 coach EMU that isn't much slower and STARTS at where a lot of passengers are boarding, they will use it since they can get a seat, or their own standing space, and having checked, platforms are available at 320m at Paddington (According to someone else on here) for 16 car units, or if I was halucinating, then a 240m platform for a 12 car unit shouldn't be a problem to find.