Students have pledged to hold the government to account over the A-level results row as the exams regulator for England dramatically suspended its policy on exam appeals.
But students have been left furious by the new system, with many losing their places on their chosen courses after not meeting the required grades.
To add to the confusion, the exams regulator Ofqual released a statement late on Saturday saying its criteria for students hoping to challenge their A-level grades on the basis of their mock exam results was "being reviewed" by its board.
It came just hours after Ofqual published guidance about its appeals process announced by Education Secretary Gavin Williamson.
Ofqual said in a statement: "Earlier today we published information about mock exam results in appeals. This policy is being reviewed by the Ofqual Board and further information will be published in due course."
Conservative MP Robert Halfon, the chair of the House of Commons' Education Committee, branded the development "farcical".
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Labour has accused the education secretary of backtracking on assurances given to students about the appeals process.
Mr Williamson gave a "triple lock" commitment that students could use the highest result out of their teacher's predicted grade, their mock exam or sitting the actual exam in the autumn.
However, in its original guidance Ofqual said that if the mock result was higher than the teacher's prediction, it was the teacher's prediction which would count.
The regulator said while mock exams did not usually cover the full range of content, the assessments took into account a student's performance across the whole course.
Labour's shadow education secretary Kate Green said: "Gavin Williamson promised to give students a triple lock, but instead he left many devastated by unfair exam results, and now his commitment to give them another chance is rapidly unravelling."
Many youngsters gathered in London's Hyde Park on Saturday for another day of protests.
Safaa Badar, who saw two of her A-level grades fall under the new system, warned the government that students won't vote for the Conservatives at the next election due to the impact the controversy has had on their futures.
She told Sky News: "I hope they consider the fact that we are the next voters, we've now turned 18, absolutely the government will be scrutinised, they will be held accountable for their actions.
"In no way we will be tolerating this… The entire situation is chaos."