Evidence is mounting that some leading English universities have lost hundreds of students - and therefore millions of pounds - as a result of the government's AAB policy.
Meanwhile, the number of new undergraduates in England could fall by up to 30,000 this year.
Figures from the Universities and Colleges Admissions Service on 11 September showed the number of students accepting places at English institutions was down 7.4 per cent on the same point last year: 30,076 fewer in terms of actual numbers.
With the average annual fee across the sector in 2012-13 estimated at £8,123, such a total could cost institutions more than £700 million in lost funding over three years.
Three factors are believed to be behind the shortfall: higher fees deterring students from accepting places; a high number of students deferring entry until next year coupled with a low number that deferred last year; and the lower-than-expected number of AAB students.
Times Higher Education surveyed English universities, asking them to supply their AAB and overall student numbers for 2012-13 on an anonymous basis.
One Russell Group university is 260 students short of its predicted AAB numbers and around 500 short of its total undergraduate numbers last year.
Another Russell Group university is currently 160 short of its predicted AAB numbers, and is 400 down on total student numbers last year.
Another less-selective university that is not part of any mission group told THE that it was 700 students down on last year's total.
The AAB system allows universities unlimited recruitment of students with those grades or better in A-level or equivalent qualifications.
But universities with high proportions of AAB students had their "core" student number controls for non-AAB students drastically cut - meaning they could not make up any shortfall in AAB students by dropping grade requirements.
The apparent failure of the system could prompt a row between selective institutions and David Willetts, the universities and science minister who introduced the AAB system in the hope that top universities would expand.
The AAB shortfalls reported by the Russell Group universities suggest a sector-wide shortfall of between 5,000 and 10,000 on predicted numbers of AAB students, which had been estimated at 85,000.
The Higher Education Funding Council for England was tasked by the government with estimating the number of AAB students. If Hefce has overestimated the total, it would lead to the overall number of places in the sector being cut - but would also deliver a financial saving for the government.