When will she have time for Fortnight?
I don't think people who have a kid that actually wants to do 4-6 hours a sports a day really understand that not only can they handle it but it is healthy.
My son did this type of schedule his whole life. Soccer and football, basketball and indoor soccer, lacrosse and soccer
He just thrives on running, being outside, being part of a team... he loves it.
If that is her thing and you family can handle the schedule I would do it.
You child wants to get up before dawn to do something healthy. Be proud.