Meanwhile, I have checked out Victoria website, and the rules I found are the following ones:

Eligible flights: All flights operated by TAM.

Eligible booking classes (and class factors):
- Economy: Y, B, M, V, K, W, I, H, Q, Z, S, O, X (x 1.0), L (x 0.0 (!))
- Business: C, J, P (x 1.5)
- First: F (x 2.0)