I don't think there is a maximum in the T&Cs however, in practice, availability and MCT does restrict what's doable . I've successfully put 3 then 4 segments per day on consecutive days:
CHC-MEL-SYD-BNE
BNE-SYD-MEL-SYD-OOL
I tried to add more by going via PER, DRW, ADL, etc., but couldn't make...