'New 125mph trains' for the mainline dictates Bi-mode I imagine. I can't see DfT signing off on high-speed express DMUs for a route that's electrified for that much of its length. The question is whether it's an adaptation of the IEP, a 125mph Bi-mode version of the 745 or something else entirely. Given Abellio's approach to Anglia I think the former is probably unlikely.
'Refurbished modern 12-car express trains' - so not 125mph and not new build, suggests 379, 360/1 or 350/2 I imagine. Unless heaven forbid they transfer the 321 Renatus fleet instead! December 2020 does tie in with the (original) proposed withdrawal date of the Anglia fleet.
No mention of change of stock for what's left of Norwich - Liverpool, so I imagine the 158s are staying put, which makes sense.
The smaller routes all list 'refurbished modern trains' - make of that what you will but I suspect inclusion of the term modern excludes 153s and 156s. What's left for them to use, 175s? ex-LNWR 170s?
125mph Bi-mode also add Bombardier to the list.
modern refurbished ex LNWR 170s and ex TfW 158s