This appears to me to be similar to the Western Force Extended Player Squad (EPS) players as a way of retaining young players as part of the program. I doubt if these players are replacing squad members or having a major impact on the salary cap.
In WA the WF Academy is usually for U20 players (usually post secondary school) - but there is talk about extending an ongoing structure and P/T development down to U18 and U16.
In WA the Force Academy players train with the main WF player squad.
The EPS players are treated in the same way as other F/T squad members.
However, from the limited discussions I've had in this area they are payed at a lower level (with some development $s from RA which is outside the salary cap) with little chance of frequent game time - more of a development position. But if good enough, and needed, then they could be playing.
It would appear that at the WF, some of the EPS squad (Makara and Pugh) are being transferred into the main player squad. I would expect other upgrades to be announced.