He warned that failures of this magnitude must carry administrative consequences for the firm involved.
"Small errors can result in serious consequences for school leaders, and the same should be expected of Pearson and everyone responsible for test and exam results," he added.
Association of School and College Leaders General Secretary Pepe Di'Iasio stated the delay would force school staff to manage administrative workloads during their scheduled summer break, calling it a "complete shambles."
Di'Iasio noted that the delay directly penalizes families who are waiting for final academic documentation.
"Parents and children now face an increased wait for these results, with all the anxiety this entails, through no fault of their own," he said.
Whiteman recalled that he had previously sought verification from the Standards and Testing Agency regarding the transition of the contract from previous supplier Capita.
"Reassured that everything was on track," he said, but demanded accountability for the systemic breakdown during this inaugural testing cycle.
"Clearly, though, something has gone badly wrong and Pearson has questions to answer. We would expect serious consequences to follow," Whiteman added.
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Pearson's Response and Marker Concerns
A spokesperson for Pearson issued an official statement acknowledging the operational disruption and offering an apology to the markers managing the platform, saying "unreservedly."
An anonymous marker reported to the BBC that internal system deadlines shifted repeatedly throughout June, causing significant administrative strain.
"Just trying to keep up," the marker said, adding that she maintained her workload solely to ensure students received their anticipated July documentation.
