This is a review, not an appeal. Review basically means that they need to show that the independent panel are either incompetent or biased, which won't be an easy task.
To be inline with salary cap this season, they have until around June I think, to get themselves under. So they can keep their squad, and then need to drop under closer to the end perhaps.
Breaking contracts could be interesting.
We also need to remember that if they can stop the joint investments, then that will bring down the bills too. No need to break the salary contract they signed upto when joining the club, but there may be other cotnracts involved.