Many people don't have projects where failure can be so publicly disruptive and scrutinised. Many of the projects that fail just never get discovered, buried in the back of reports and statistics.
I expect that something has knocked the Critical Path for this project. It's not easy to get spare parts and a redundancy plan in play on Christmas Day and insurance costs money. Projects can quickly become an ACE and a reason why not to do things. Network Rail needs to take risks to get these projects done. Whilst they deserve scrutiny for the amount of public money involved, I think the best thing they need is that they need support.
I assume that there will be vacancies shortly at Network Rail and its subcontractors for those of you looking for a challenge
I accept that major projects can go wrong. I'm not blaming Network Rail for this. It's the TOCs response to it that has been so woefully inadequate.