This dispute concerned the terms for interim payments between a contractor and sub-contractor regarding the construction of a university building. The contract required that the sub-contractor apply for interim payments and a payment schedule to the contract provided for dates for each stage of the process. The general approach was for payment to become due 14 days after the application was made by the sub-contractor, and for the contractor to issue a payment notice or pay less notice within 5 days of payment becoming due. This was applied by the parties between March 2015 and September 2015. However, for October 2015 the schedule provided that the assessment date was 2 November, the due date was 16 November, but the payment notice date was 23 November, and the pay less notice date was 20 November. The contractor issued its payment notice on 23 November and the sub-contractor argued that this was out of time because it was not issued within 5 days of the due date (i.e., by 20 November). The contractor argued that the dates in the schedule applied. The judge, construing the contract, found that the schedule applied but that there was an obvious error in the payment notice date of 23 November, which should have been 20 November. Accordingly, the contractor had not served a timeous payment notice.