The Victorian Civil and Administrative Tribunal has overturned a stewards' ruling to freeze prizemoney won by trainers Danny O'Brien and Mark Kavanagh in black-type races, pending their cobalt hearings.

Both O'Brien and Kavanagh are due to face the Racing Appeals and Disciplinary Board to answer charges relating to elevated cobalt levels, with the hearings to start on November 30.

Both trainers had their prize money percentages in black-type races frozen by stewards after show-cause hearings in August.

But the VCAT ruling means they will get their percentages back from the spring carnival.