Reported progress against the audit record at Crossrail
A reconciliation is the short format here. Two public documents describe the same project and disagree. The table is the piece.
29 August 2026
| Measure | What the plan asserted | What the audit record found | Gap |
|---|---|---|---|
| Milestone attainment, 2019 to early 2020 | Full attainment | About 30 percent | 70 points |
| Milestone attainment, Sep 2020 to Apr 2021 | Full attainment | About 90 percent | 10 points |
| Signalling update for trial operations | On plan | Late | 3 to 8 weeks |
| Central section opening | December 2018 | May 2022, actual | 41 months |
Attainment and slippage figures from National Audit Office reporting.12 The auditors note that the attainment metric also reflects new milestones being added, so it is a measure of plan quality as much as of site productivity. That is the point.
A milestone plan is an assertion of full attainment. Every milestone in it is dated as though it will be met, which is what makes the comparison legitimate: the plan is not a forecast with error bars, it is a claim.
Through 2019 and into early 2020 the audit record found roughly 30 percent2 attainment on average, sustained for more than a year, while the program continued to plan on more optimistic productivity. In 2019 the auditors had already concluded the program had no realistic plan to complete1.
Then the second row. After the detailed replanning of August 2020, attainment ran at roughly 90 percent2. Same contractors, same railway, sixty points of movement in a metric that most organizations read as a productivity measure.
It was never only a productivity measure. Attainment is the distance between what a plan claims and what a site does, and either side of that subtraction can move. Crossrail's moved because the plan was rebuilt to describe the work that actually remained, including the assurance documentation and testing precedence that the earlier plan had not carried.
Neither number was ever hidden. Neither party was lying. The milestone plan and the attainment record were produced by the same organization, for the same program, in the same months, and each was correct about what it measured. One measured intent, the other measured outcome, and nothing in the reporting structure obliged anyone to put them on the same page for over a year.
The general form: a program in trouble usually knows. The knowledge sits in artifacts that no single review reads side by side. Reconciling two of them takes an afternoon and beats most forecasting.
The full essay: the railway that existed before it worked.
Sources
- National Audit Office, Completing Crossrail (2019).
- National Audit Office, Crossrail: a progress update (2021).