Lessons Learned: Change Process Misuse in a Critical Path Environment

A major international consortium was engaged to design and construct multibillion-dollar urban rail project under a 60-month EPC contract. During delivery, it sought a 540-day extension of time, citing disruption and delay from 36 Employer-issued Change Notices (CNs). The claim framed the CNs as cumulative and overwhelming, asserting that they rendered the original delivery sequence unworkable.

The consortium behind the claim included some of the world’s largest and most experienced firms—among them, a top-three global building contractor, a leading rail equipment supplier, a prominent national contractor, and one of the largest international design houses.

Our review of the cost overruns revealed a fundamental misstep early in delivery: the lead contractor terminated the internationally renowned design consultant responsible for the 30% concept design complete at contract award and chose to deliver the remaining design work in-house. Rather than building on the approved early design and progressing to tender within three months, the new team, assembled via open recruitment, took over two years to complete the design documents. This single decision delayed procurement and execution across all downstream packages and masked the true source of program failure.

• The claim presented a sweeping narrative that CNs created chaos in the design process, derailed the sequence of works, and forced significant redesign. But the contemporaneous project records told a different story:

• Most CN’s were issued early (before 30% design) and were not integrated by the contractor into their initial or formal design submissions.

• Contractor delay on design milestones occurred independently of the CN’s. The delays were traced to internal resourcing and non-compliance issues.

• The contractor failed to respond to many CNs within the agreed timeframes or submitted partial pricing. Several CNs were ultimately cancelled, or approved without any extension to the program, and the contractor, in its own firm price proposals, confirmed “no impact to completion date” if approvals occurred on or before set dates.

• Only 2 of the 36 CNs were analysed in the contractor’s own delay report; neither showed any delay to the project’s critical path.

• Claims for disruption and redesign were not particularised, no detailed demonstration of rework, resourcing impact, or lost productivity was provided.

Our involvement identified the root cause of the delay and cost overrun as the exclusion of the international design house from the consortium, which proved critical to resetting the basis of the dispute. Our findings gave the High Commission and oversight teams clarity on the underlying issue, and helped steer the $4B+ claim, toward early settlement on far more realistic terms.

To support the commercial position, we carried out a forensic mapping of all 36 CNs to the critical path, assessed each against the contractor’s design and delay submissions, and reconstructed the timeline of the change process. Our findings confirmed:

• No CN individually or cumulatively drove critical path delay.

• Most CNs fell within the normal scope of design development.

• Many of the claimed delays stemmed from late or fragmented contractor submissions, poor interface coordination, and internal rework.

• The claim constituted a global delay narrative without particularised linkage between the CNs and actual time slippage.

Our report recast the claim not as a delay caused by excessive change, but as a breakdown in the contractor’s use of the agreed change process—highlighting failure to comply with time-bars, submit proper proposals, and distinguish employer-driven delays from their own internal issues.

• Do not remove a proven design team at contract award. Replacing a globally experienced design house turned what should have been a short progression to final design and tender into a two-year delay that set back the entire delivery program. The decision undermined continuity, design maturity, and interface clarity across every discipline.

• Continuity is critical. Concept design isn’t just drawings, it carries institutional memory, stakeholder alignment, and coordination logic. Starting over with a new team erases this and forces rework, clarification, and delays that ripple through procurement, approvals, and construction.

• Delays in design approvals were also caused by fundamental changes in the (late) design. Even when Change Notices are formally responded to or approved on time, they do not recover program momentum if the base design itself changes and is years late.

• In this case, the largest cost and delay exposure did not arise from external instructions or change requests; it came from a strategic design misstep made internally at the very start.

Note: Our analysis allowed the parties to pivot away from the 540-day claim and focus instead on a more accurate, event-based reconciliation—preserving the integrity of the program and the contractual framework.