The exchange student agreement established between Ember Academy and the various nations states: The young members of the royal families from all nations can receive benefits and teaching conditions at the academy that are fully on par with those of formal students, and after completing three years of cultivation, they may return to their own countries without obstructing Ember Academy.
The latter point was heavily emphasized in the agreement by the nations.
They were worried that Ember Academy might lure away their outstanding young members, even though such a possibility was extremely slim.
As a price, each country would pay a hefty exchange tuition fee.
This was different from the Blue Star era when the training camp took in exchange students like Anna. Back then, the purpose of the training camp was to cultivate a group of pioneers to spread the correct path of mysteries, reducing the high awakening casualty rate during the early Era of Mysteries.