Fictional practice case. Enable JavaScript for interactive classification and scoring, or work through the evidence and model explanation below.
The scenario
- project
- North Line Water Treatment Expansion (fictional)
- reporting Period
- Change Event CE-24 — electrical room redesign
- data Date
- Accepted update — 31 August 2026
- contractual Finish
- 15 March 2027
- protocol
- For this training case, technical completeness is evaluated before entitlement. An unexplained calculation-setting change, nonreproducible impact, or omitted materially parallel path requires correction before the TIA can be relied upon.
Evidence register
source-schedule / Unimpacted source schedule
Prior: August 2026 update accepted on 8 September, before the redesign directive.
Current: The TIA begins from that accepted native file and its 31 August data date.
Support: Approval log, file checksum, and source-file archive all reconcile.
status-preservation / Status preservation
Prior: The accepted update contains 1,842 activities and the approved August status.
Current: The impacted copy retains the same activity status, remaining durations, and data date outside the fragnet.
Support: A native-file comparison identifies only the inserted fragnet, its ties, and one calculation-setting change.
event-chronology / Event chronology
Prior: RFI-117 raised the clearance conflict on 20 August.
Current: Directive CE-24 issued 9 September; revised design released 23 September.
Support: RFI, directive, design transmittal, and meeting minutes establish the dates without deciding responsibility.
fragnet-anchor / Fragnet insertion
Prior: The event must enter from the redesign directive and drive the affected electrical-room work.
Current: The first fragnet activity has no predecessor; its finish ties only to cable pulling, bypassing equipment setting.
Support: No modeling note explains either open boundary or the bypassed installation sequence.
fragnet-durations / Fragnet duration basis
Prior: Design, fabrication, installation, and test durations require contemporaneous support.
Current: The fragnet uses 10, 25, 8, and 3 working days for those activities.
Support: Contract review period, vendor quote, crew production sheet, and commissioning procedure support each duration.
calculation-options / Scheduling options
Prior: The accepted source schedule uses retained logic for out-of-sequence progress.
Current: The impacted file uses progress override.
Support: The TIA narrative does not disclose, justify, or isolate the effect of the setting change.
impact-result / Reported completion impact
Prior: Unimpacted recalculation forecasts 15 March 2027.
Current: Impacted file forecasts 2 April 2027; the report states an 18-workday impact.
Support: The five-day project calendar contains only 14 workdays between the two forecast dates.
parallel-path / Parallel path and concurrency screen
Prior: The accepted update has a separate chemical-feed path two workdays behind the longest path.
Current: The TIA states that no parallel delay exists but provides no float-path or contemporaneous-progress comparison.
Support: The native file shows late chemical-feed submittals during the same analysis window.
Model review
The analysis uses the accepted contemporaneous update.
The archive, approval record, checksum, and TIA source file all identify the same pre-event schedule.
This is a supported source-schedule control. It establishes the model being impacted without deciding whether the event is excusable or compensable.
Activity status is preserved outside the fragnet.
The comparison shows no rewritten actuals or remaining durations in the existing network.
Preserving the accepted status makes the impact comparison auditable. The separately identified scheduling-option change still requires its own finding.
The event dates are supported by contemporaneous records.
The RFI, directive, release, and minutes establish a usable chronology.
The records support when the modeled event occurred. They do not, by themselves, establish contractual responsibility or entitlement.
The fragnet is not dynamically anchored to the full affected sequence.
Its open start and bypassed equipment-setting work can change both the event timing and downstream impact.
A prospective TIA depends on a technically defensible insertion. The fragnet needs an event boundary and complete ties to the work it is intended to affect.
The fragnet durations have a traceable basis.
Contract, vendor, crew, and commissioning records support the modeled working durations.
Supported duration assumptions make the modeled work reviewable. The reviewer should preserve the records and still test the logic and calendar application.
A calculation setting changed between comparison files.
Progress override replaces retained logic only in the impacted model.
The unimpacted and impacted calculations are not like-for-like when an unrelated scheduling option changes. Its effect must be removed or separately quantified and disclosed.
The reported impact uses the wrong time unit.
The calendar-date movement is 18 days, but the applicable calendar contains 14 working days.
The report must distinguish calendar days, workdays, and the calendar used. A mislabeled result is not reproducible and can overstate the quantified impact.
A materially parallel path was dismissed without analysis.
The near-critical chemical-feed path had contemporaneous late work but no comparative path analysis.
Parallel or concurrent delay cannot be resolved by assertion. The technical package should show the relevant path, status, float, timing, and the contract-specific basis for any concurrency conclusion.
Model disposition and closeout
Revise and resubmit
The corrected TIA should anchor the fragnet to the directive and complete affected sequence, restore identical calculation settings or separately quantify their effect, report the completion delta in the correct calendar unit, and evaluate the contemporaneous chemical-feed path. The resubmission should preserve both native files, comparison outputs, event records, fragnet basis, schedule logs, and a change register. Technical acceptance would still not decide notice, causation, concurrency, excusability, compensability, or damages under the governing contract and law.