Most kids will resist change because they want to stick with what is familiar.
25 hours is excessive at level 6, and unnecessary. If she is complaining it’s too many hours now, it’s unlikely she will want to do Elite. And it’s rare fir a gym to ask for so many hours at this level unless Elite is the goal.
BUT the school thing is also a major issues. Of course the hours in the gym would burn her out if she is doing assignments until midnight. If she was getting enough sleep and recreation time then she might feel differently.
People are often quick to say “cut back in gym” but why not cut back on school work?
I would absolutely not allow my child to be staying up until midnight doing assignments. I would tell the school it’s not happening, I would allow for a reasonable amount of homework and then the books would go away.
Doing that much homework is VERY damaging for a child health. Sleep deprivation is deadly and will impact her growth. But in Order To develop well children need time for socialisation, imagination, sports and play, down time etc.
I know things are different in the US because homework is part of their grades and schools can force them to repeat grades. Neither of these things is the case in Australia. But that’s just unhealthy and crazy.