In Mace Construct Ltd v Baltic Investment Holdings Ltd [2026], the Technology and Construction Court (TCC) addressed how prospective and retrospective assessments of extensions of time (EOTs) interact – and the power of adjudicators (or courts/arbitrators) to subsequently open up, review and revise extensions granted during the works.

Below we examine how the dispute arose, the parties' arguments, and how the TCC reached its decision.

Case overview: Mace v Baltic and the EOT dispute

  • The dispute arose under an amended JCT DB 2016 contract for refurbishment works to the Baltic Exchange Building at 38 St Mary Axe, London.
  • In December 2024 the Employer's Agent granted EOTs to Mace totalling seven weeks and five days.
  • In a subsequent adjudication the adjudicator "opened up" that decision and reduced that extension to zero.
  • Mace commenced Part 8 proceedings for declarations on a range of issues, including as to the incorporation of documents, design responsibility, planning risk allocation, and the EOT mechanism.
  • Declaration 7 (which is the focus of this article) was sought in the following terms: "An adjudicator and/or the court does not have the power to fix a completion date which is earlier than that which has previously been fixed by the Employer's Agent, by virtue of clause 2.25.4 and/or clause 2.25.5.2 of the Contract".

JCT extensions of time: the contractual framework explained

The contract contained the standard JCT clauses governing EOTs, which set out a tiered EOT regime.

Clause 2.25.1 requires the Employer / Employer's Agent to make a prospective assessment: upon receiving a notice and particulars of delay, it must fix such later completion date as it "then estimates to be fair and reasonable".

This is an inherently forward looking exercise, requiring the Employer to estimate the future effect of Relevant Events that have already occurred.

After the completion date has passed, clause 2.25.5 provides a review mechanism. This gives the Employer not merely the power but also the duty to review the overall position with respect to EOTs, and to fix a later or (for Relevant Omissions) an earlier completion date, or to confirm the date previously fixed.

The parties' submissions: can an adjudicator fix an earlier completion date?

The Court endorsed the "entirely orthodox" position advanced by Mace that JCT clause 2.25.1 requires the Employer / Employer's Agent to conduct a prospective exercise. This involves estimating the effect, in the future, of Relevant Events which have occurred.

However, Mace then made what was described in the judgment as the "bold further submission" that an EOT granted under clause 2.25.1, however incorrect, could never be reviewed by an adjudicator or the court, on the basis that a tribunal would inevitably be looking at the matter retrospectively – knowing how matters had turned out – and would therefore be unable to carry out the prospective exercise that clause 2.25.1 requires.

Counsel for Baltic countered that this led to the "somewhat surprising" conclusion that the Employer would be eternally saddled with an erroneous extension of time. Further, it ignored the adjudicator's power of review under paragraph 20 of the Scheme for Construction Contracts (England and Wales) Regulations 1998 (the "Scheme"), which empowers an adjudicator to "open up, revise and review any decision taken or any certificate given by any person referred to in the contract".

Baltic submitted that this empowered the adjudicator to "stand in the shoes" of the Employer/Agent when performing the clause 2.25.1 duties.

TCC decision: power to review exists; the task remains prospective

The Court agreed with Baltic and declined to grant Declaration 7. Adrian Williamson KC (sitting as Deputy Judge) held that:

  1. The adjudicator can open up, revise and review an extension of time granted under clause 2.25.1, but in doing so must carry out the task which that clause requires—namely, a prospective assessment in response to the notice and particulars submitted under clause 2.24.
  2. The Court accepted that this may be a difficult task for the adjudicator, who must "travel back" to the time at which the notice and particulars were submitted.
  3. However, these were characterised as points going to the evidence and procedure that the adjudicator should consider and adopt - they were "not objections of principle" to the adjudicator carrying out his reviewing function under paragraph 20 of the Scheme.

The Court endorsed the orthodox position that clause 2.25.1 requires a forward‑looking exercise. It also recognised the analysis set out in Keating, put forward by Mace, that prospective decisions can over- or under-estimate delay and that clause 2.25.5 provides a review mechanism which may correct underestimates, while earlier dates can only be introduced to reflect later Relevant Omissions.

None of that, however, renders an Employer's in‑works EOT decision immune from scrutiny. A tribunal may review it; the constraint is the basis of the review, not the existence of jurisdiction.

Key takeaways for EOT disputes

  • Jurisdiction stands: the prospective nature of clause 2.25.1 does not deprive adjudicators or the Court of being able to review an assessment made pursuant to that provision. The "retrospective tribunal" problem is addressed by evidential discipline, not by denying jurisdiction.
  • Build the ex ante record: parties should prepare and present contemporaneous programmes, progress records, and forecasting materials as they stood when the clause 2.24 particulars were submitted. This also underscores the importance of contractors submitting clear and timely notices of delay / likely delay.
  • Prospective lens on review: expect adjudicators to "stand in the shoes" of the Employer/Employer's Agent and to explain how they have neutralised hindsight in reaching a fair and reasonable assessment.

    This might be easier said than done. For example, an adjudicator / arbitrator may struggle to reconcile the conclusion, reached on the basis of a prospective delay analysis, that a contractor was due a 50 day EOT with clear retrospective evidence that the actual delay incurred was, say, only 30 days. Evidential problems may also arise in relation to what was known at the time the assessment was made. However, there may be circumstances which justify such a conclusion, e.g. where there is evidence of the contractor mitigating the delay or accelerating the works. Ultimately, the outcome will always be contract and fact sensitive.

For advice on extensions of time, or construction disputes generally, please get in touch with Daniel Wood or Mike Stewart.