I heard the same thing posted by Ettore; the issue is not the waiver that the conservatory took. The fact is that pre-academics are not AFAM. Conservatories have become AFAM, so the teachers themselves are not authorized to teach pre-academics.
There is a heated debate on the issue of pre-academics, mainly because the two most representative unions (CGIL and UNAMS) say diametrically opposite things. There is even an opinion from the State Attorney General's Office (found on the UNAMS website) that interprets Law 508 in its own way and claims that pre-academics are not provided for (whereas I, having read the law for 12 years, maintain the contrary).
The point is very simple: for now, the law allows any activity that is approved by the Academic Council (of which I am a member in my conservatory). In Conservatories where the establishment of pre-AFAM courses is approved, they are legal. Why? Because the internal approval is then validated by the Ministry itself (sic!).
Therefore, as long as no decree is issued banning them, they are fully legitimate.
Then, we can discuss the status of the teachers. In my case, the teaching hours are filled first with two-year programs, then three-year programs, then old system programs, and finally, if there is a vacancy, with pre-academics. In other conservatories, they are assigned to external teachers (I don't know with what money...), while in others, they are not activated.
This is the 1999 reform (there would be at least 10 other things to discuss).