London - Bristol Parkway - Cardiff is being electrified
Bristol Parkway - Bristol is being electrified (as the additional two/hour from London to Bristol will run this way).
So I'd expect the short chord through Patchway will get wired too.
Therefore I think that's a decent chance that the Cardiff - Portsmouth will be split into:
- Cardiff - Bristol (four coach EMU)
- Bristol - Portsmouth (DMU)
(thus allowing the Portsmouth service to maybe be doubled up?)
Frustratingly its not *that* far to electrify from Bath to Southampton, but I guess that depends on Basingstoke - Exeter electrification