EOT, prolongation and disruption: separating time entitlement from cost recovery

Extension of time, prolongation and disruption are often discussed as if they were one claim, but they answer different questions. EOT concerns the contractual completion date and whether qualifying events delayed completion. Prolongation concerns additional time-related cost caused by an extended project duration. Disruption concerns loss of productivity or efficiency, which can occur even without extending the final completion date.

An EOT submission should begin with a clear event chronology and contractual basis. The team should identify the planned activity, actual event, responsible party, notice, mitigation, programme status before the event and resulting effect on completion. Merely demonstrating that an Employer event occurred does not automatically prove critical delay; the link to the programme and completion path must be shown.

Programme quality matters. Baseline logic, calendars, constraints, progress updates, actual dates and changes in sequence should be credible enough to support causation analysis. If the programme is not updated contemporaneously, later delay analysis becomes more dependent on assumptions. The chosen analytical method should suit the contract, available records and stage of the dispute rather than being selected only because it produces a favourable number.

Prolongation cost should then be derived from the period and resources actually affected. Site management, offices, camps, security, utilities, equipment standby, insurances, guarantees and other time-related costs may continue during an excusable compensable delay, but each category needs contractual and factual support. Home-office overhead or financing claims require particular care and should not be assumed from formulae without checking the governing contract and evidence.

Disruption analysis focuses on productivity. Changed sequences, repeated mobilisation, congested work fronts, out-of-sequence work, excessive inspection interruptions, late information or cumulative changes may increase labour or equipment hours without directly extending completion. The strongest analysis compares affected and unaffected performance where reliable data exists, while also controlling for contractor-caused inefficiency and other confounding factors.

The commercial forecast should keep time entitlement and cost recovery separate until each is assessed. An approved EOT may protect against delay damages without automatically establishing full prolongation reimbursement. Conversely, disruption may create additional cost even where completion is maintained through acceleration or resequencing. Separating the analyses produces a clearer claim and prevents one weak element from undermining another valid entitlement.