I have wrestled with so many weasel words and 'could / possibly be' in this report that I realise that there is no commitment whatsoever to anythiing that you could bank on.
Here's just one example of a section and there are scores more.
"Avoiding Over-Specification
5.12 The Oakervee Review highlighted the need to avoid overspecification when planning further sections of the UK’s high speed rail network, as it can become costly to make changes as the design becomes more mature.
5.13 HS2 Ltd and Network Rail have iterative processes to sifting route options, to better understand the benefits, costs, engineering feasibility, environmental impacts and other impacts arising to determine the suitability of possible concepts and the resulting route alignments. This process has enabled outputs to be reviewed to understand the journey times, frequency, capacity and performance metrics that would be delivered by each concept to assess its contribution to the strategic case and the value for money outcome.
5.14 This iterative approach to specification development has enabled some concepts to be revised, so that rail outputs better represent the forecast travel market or demonstrate a stronger value for money case.
5.15 Many possible interventions outlined within the IRP are subject to further work being completed to determine they represent the right choice on their respective corridors. While further work is performed on these corridors, the same iterative approach will be taken to ensure the Government’s strategic objectives are met, while still delivering strong value for money and benefits for the communities in the Midlands and North."
GRIP rules OK (at least, never mind the Treasury) and you could not even garantee MML electrification to Sheffield given the above, and that isn't due to complete until sometime in the 30s.and won't be started until the late 20s (see their table Figure 9 on page 134 above the section just quoted).