Thousands of access students expecting to receive the Pounds 1,000-a-year mature students' allowance have had their hopes dashed despite an apparent reprieve earlier this year.
In March, the Department for Education said that access students going straight into higher education would still able to claim the allowance during their degree, even though the Government has abolished the grant for all new students.
However, the Parliamentary amendment regulation laying down conditions of eligibility for those currently on access courses says only full-time students can receive it.
The National Union of Students says this means most access students will be excluded, since they study part-time because of another piece of legislation - the 21-hour rule preventing benefits from being claimed by full-time students.
"We feel the DFE has reneged on its commitment to access students," said Anne Sims of the NUS.
"Thousands of people embarked on courses in September 1994 with no idea the assurances they thought they had got would no longer be there this September."
Labour is seeking to revoke the regulation and further and higher education spokesman Bryan Davies has tabled a parliamentary question to ask what help the government will offer to part-time access students who had been expecting the allowance.
In another welfare clampdown, the NUS has also been told by the Department of Social Security that it will act soon to prevent students who break their course from claiming benefits.
The Appeal Court ruled in February that students with written proof of intercollation, temporary non-attendance due to illness or other good cause, could claim income support or housing benefit.
A DSS spokesman confirmed: "There was a court ruling and because of that the regulations will be amended to restore the policy intention." The revised rules will come into force next month.
The moves against benefits come as the NUS has said students of all ages would be better off financially on the dole than in education.
It said the average weekly income from benefits for an unemployed 18- to 24-year-old is Pounds 71.80, compared to Pounds 62.88 on grant plus loan. The average welfare payment for a 25- to 50-year-old is Pounds 81.15 a week, while the grant/loan amount stays at Pounds 62.88.
While benefits remain at Pounds 81.15 for unemployed people aged over 50, students of this age are only eligible for a grant - a maximum Pounds 36.25 a week.
Labour responded by indicating it would restore state benefits to students during the summer if it came to power.
Bryan Davies said: "Students have got a low income over the whole year, but at certain times of the year they are very poor.
"We have got to see students during that period treated in similar structures to other people who need support and that is the principle under which we are working."