Examiners warned the Schools Secretary Ed Balls that there is "no guarantee" that pupils will not see a repeat of delays for Sats tests results again next year, it was revealed today.
Some pupils were left waiting months for their marks from the exams sat by 11- to 14-year-olds after a series of blunders including a failure to train markers on time.
The company running the tests, ETS Europe, was sacked from its five-year contract in August after an inquiry blamed it and Qualifications and Curriculum Authority for the hold ups.
The QCA has now warned Mr Balls that the rush to appoint a new company to run tests for 11-year-olds in 2009 has meant there is no time to test the marking systems to ensure they do not collapse again.
Edexcel have been given the contract and have agreed to deliver 99.9 per cent of test results to candidates by 7 July 2009.
But Chief Executive Ken Boston - writing to the minister before his suspension in mid-December in the wake of a damning inquiry into the fiasco - warned "that whilst the supplier is committed to achieving it (the deadline), there is currently no guarantee that events will not cause them to miss it".
He stated that the speed with which Edexcel had to be appointed has meant that the fine details of the contract will have to be worked out after it is agreed.
The risk of missing the deadline will, he said, "be at its greatest in the crucial and short period between the beginning of marking and the completion of results data".
In a reply Mr Balls agreed that the contract with Edexcel should go ahead but urged the QCA to arrange for "effective contingencies" to be put in place, "thereby reducing the likelihood and impact of serious risks to delivery".
But Mr Boston's reply warns the Minister that the steps the QCA can take to prevent delays are limited.
"We will do all we can to mitigate risk, but it is important that I re-emphasise to you that the risks in this process are high.
"In the restricted time available to us it will not be possible to develop mitigations to the level that either you or I would wish. In particular during the crucial short period between the tests being sat, and the results being published on or by 7 July, the only meaningful contingency available is a delay in publishing the result."
Mr Balls has asked the QCA to give his officials full access to the contractual terms and to give him a progress report in January.Reuse content