I assume we're talking about statutory appeals. According to the new Code of Practice:
2.2 Admission authorities must publish their appeals timetable on their website by 28 February each year.
- which is not to say that they've got round to it yet!
If the information isn't there, ring them up and enquire. (Best not to talk about 'non-qualification' - from their point of view it's just an 'appeal'.)
.... or if it's all done by letter/paper submission
If it's a statutory appeal, you must be invited to attend. (The appeal can go ahead in your absence on the basis of your written case, but you could be seriously disadvantaged if you don't attend.)