Candidates who do better than expected could find themselves in trouble if they abandon the university place they accepted earlier in the year and start looking for something better, the head of the admissions service has warned.
The warning raises the possibility of students being sued for breach of contract by disappointed universities, though in reality few are likely to pursue such an extreme course of action.
However, admissions officers say they will put pressure on students who have the right grades to take up their place but who decide to go elsewhere. Universities are legally bound to give candidates a place if they accept an offer and make the grades, they say, and students should be made to stick to their side of the deal.
The problem has arisen this year because for the first time there is one admissions system for old universities and former polytechnics.
In the past, students could fish around for places in two different admissions systems, but now they hold two offers under the new Universities and Colleges Admissions Service (Ucas) and must take up the best one for which they have the right grades.
Extra pressure has been put on universities this year by government restrictions which mean they could face penalties of up to pounds 2,800 per student if they do not meet their target numbers exactly, making them more anxious to hold students to their promises.
The only legitimate way out of the contract is to take a year off and apply again, though in reality universities will find they have little option but to release candidates who want to go - a reluctant student is unlikely to be a great asset. Tony Higgins, chief executive of Ucas, has written to all universities to warn them not to accept students who are already pledged elsewhere. He has advocated a system under which students would apply after receiving their A-level results, thus eliminating the need for contracts which are struck before students have even sat their exams.
There are fears that if one or two universities step out of line, then the rest will follow suit and a free-for-all will result. Among the newer universities, several admitted that they could lose students if others acted unscrupulously. Kay Coulson, admissions officer at the University of Derby, said that students who wanted to go elsewhere would be 'counselled very carefully'.
She added: 'They made an original choice of our university, and they must have had a reason for doing that. But at the end of the day you cannot force them and it would not be very productive to do so.' Steve Kendall, head of admissions at the University of Luton, plans to take a harder line. 'I think the basic response has to be 'no'. Otherwise we do not have an admissions system.'
The Independent and the Independent on Sunday start exclusive publication of the full official Ucas listings of vacancies in universities and colleges on 24 August.
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