Ganguly, the Indian captain, was suspended for two Tests by the ICC match referee Clive Lloyd for his team's slow over-rate during Saturday's one-day international against Pakistan, which breached one of the ICC Codes of Conduct. As this was Ganguly's second such trangression of the year, he was handed an automatic ban and he will miss both Tests against South Africa if the punishment is upheld.
Castle, meanwhile, has over 30 years' experience in the areas of litigation, representative sport, national and international sports administration and management. He will have up to seven days to review a video of the match, Lloyd's reasons for banning Ganguly, and also Ganguly's grounds of appeal.
If the decision on the appeal does take a week, Ganguly would be eligible for the first Test at Kanpur. But theoretically, a decision to uphold the suspension could be taken a day before the Test, which would leave Rahul Dravid with some last-minute reshuffling.